working paper series...c61: optimization techniques; programming models keywords goal programming,...
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College of Business Administration
University of Rhode Island
2004/2005 No. 16
This working paper series is intended tofacilitate discussion and encourage the
exchange of ideas. Inclusion here does notpreclude publication elsewhere.
It is the original work of the author(s) andsubject to copyright regulations.
WORKING PAPER SERIESencouraging creative research
Office of the DeanCollege of Business AdministrationBallentine Hall7 Lippitt RoadKingston, RI 02881401-874-2337www.cba.uri.edu
William A. Orme
Gordon H. Dash, Jr. and Nina Kajiji
A Nonlinear Goal Programming Model for Efficient Asset-Liability Managementof Property-Liability Insurers
A Nonlinear Goal Programming Model for Efficient Asset-Liability Management
of Property-Liability Insurers *
By
Gordon H. Dash, Jr.**
Associate Professor of Finance and Insurance
Nina Kajiji ***
Assistant Professor of Research
JEL CLASSIFICATION
G22: Insurance; Insurance Companies C61: Optimization Techniques; Programming Models
KEYWORDS
Goal programming, Nonlinear programming, Asset-liability models, Insurance, Risk management, Property-liability insurers, Portfolio optimization
2004 By Gordon H. Dash, Jr. and Nina Kajiji. All rights reserved. Explicit permission to quote is required for text quotes beyond two paragraphs. In all cases, full credit, including notice is required.
The research presented in this paper was completed under grants from: The Office of the Provost, University of Rhode Island; and, The NKD Group, Inc. (www.nkd-group.com), the producers of the WinORSfx financial engineering software used for the application presented in this manuscript.
Nonlinear Heirachical Modeling for Insurers.
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ABSTRACT
Optimization of the firm-level asset-liability model (ALM) is an important part of enterprise risk management. In the context of the property-liability insurer we increase the credibility of the ALM by explicitly unifying the efficient management of financial risk factors across both sides of the economic balance sheet. The ALM presented in this research produces a simultaneous solution to the Markowitz mean-variance (MV) allocation of asset- and liability-side resources within a complex hierarchical goal environment. The nonlinear optimization method applied to the dual MV problem that is defined within the overall ALM is a separable program that encapsulates a vector optimized goal-program (NLGP). In addition to the identification of efficient combinations of traded assets and not-traded liabilities within a complex goal environment, the NLGP ALM also proves suitable for the extant characterization of credit, liquidity, and profit margin objectives.
1. Introduction
The liquidity strains of the late 1970s and early 1980s caused property-liability insurers
to follow the example set by the U.S. banking industry and its commitment to asset-liability
management (ALM) models as means by which to mitigate the ill effects of enterprise risk
management. For example, by the late 1980s banks had already advanced the state of ALM
frontier methods in their quest for efficient economic asset strategies given a particular liability
profile and overall business plan. In a recent review on insurer valuation, Babble (2001) noted
that while ALM tools are well developed what are lacking are useful stochastic valuation models
that unify both sides of the economic balance sheet. Asset-side stochastic model formulations
were already prevalent in the literature. In the late 1980s Booth and Bessler (1989) provided a
substantial review of relevant literature and a model extension that featured a futures-based
hedge to efficiently mitigate asset-side interest-rate risk. Almost a decade later, Boender, et. al.
(1998) produced a summary of contemporary ALM models and conveniently identified the
stylized relationships needed to simulate consistent decision-making scenarios. As researchers
entered the new Millennium model building efforts focused on two new areas: complex models
characterized by multi-criteria and hierarchical firm objectives and applications in the global
financial services industry. In the former case Babbel and Hogan (1992) and Korhonen (2001)
provide a time-line of evidence for complex hierarchical and multi-criteria decision-making. In
the latter case, Kosmidou and Zopounidis (2002) provide international evidence of prevailing
asset-side risk mitigating multi-criteria ALM in an application to a Greek bank. Dash and Kajiji
(2002) further advance the globally oriented stochastic multi-criteria ALM synthesis to include
domestic demand curve nonlinearities of an Indian bank.
Nonlinear Heirachical Modeling for Insurers.
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It is widely accepted that insurers, particularly property-liability insurers, also rely upon
ALM for the determination of efficient firm planning. In a recent review of the empirical issues
on insurer consolidations and economies of scope, Cummins et. al. (2003) synthesized the long
standing realization that property-liability insurance firms face ALM complexities that are not
dissimilar to those faced by depository financial institutions. In citing the two distinct activities
carried out by property-liability insurers -- the selling of future claims against themselves (the
issuance of insurance contracts, or underwriting) and the diversification of asset side investments
-- Babbel (2001) argues persuasively that measurable improvements to insurer value will come
from the use of improved ALMs and not necessarily from improved security valuation methods.
He asserts that, there is a deep need for a unified valuation model one that efficiently takes
into account the important financial risk factors across all major asset categories and over both
sides of the economic balance sheet. From the early ALM formulations that attempted to mesh
evolving financial valuation theory with efficient firm-level risk management, Hofflander and
Drandell (1969), Drandell (1977), and Cummins and Nye (1981) and others have continually
sought to improve asset-side property-liability ALM specificity.1
1 See Lamm-Tennant, J. (1993). "Stock Versus Mutual Ownership Structures: The Risk Implications." Journal of Business
66(March): 29-46. for a discussion on organizational form and the management of firm-specific risk. BarNiv, R. and J. B. McDonald (1992). "Identifying Financial Distress in the Insurance Industry: A Synthesis of Methodological and Empirical Issues." Journal of Risk and Insurance
49(4): 543-574. provide a focused review of specific ALM methodologies that targets insolvency problems within the insurance industry. Similarly, Petroni, K. R. (1992). "Optimistic Reporting in the Property-Casualty Insurance Industry." Journal of Accounting and Economics
15(4): 485-508. presents evidence that supports the adoption of ALM approaches by documenting how weak insurers are more prone to forego the use of ALM methodologies as way to avoid the inherent objectivity the method brings to the description of adverse news (eg., required estimates of claim losses). Cummins, D. J., M. A. Weiss, et al. (1999). "Organizational Form and Efficiency: An Analysis of Stock and Mutual Property-Liability Insurers." Management Science
45: 1254-1269. focus on organizational form and efficiency for both stock and mutual property-liability insurers.
Nonlinear Heirachical Modeling for Insurers.
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Although it is not strictly an insurer-based model, Sharpe and Tint (1990) extended the
analysis of the firm s across-sheet balance sheet MV problem. In an effort to capture liability
side effects, the Sharpe and Tint model focused on the firm s net surplus. The surplus model
was a notable extension but it has limited practical significance. The model s introduction
preceded contemporary economic realities such as the passage of the Financial Institutions
Modernization Act of 1999 (FIMA), emerging international opportunities, and new technological
innovation. The rapid change to the insurer s economic landscape have fueled model builders to
renew their focus on how to best estimate the cost of equity for insurers with increasingly diverse
underwriting portfolios. Cummins and Phillips (2003) address the issue through the
introduction of the full-information industry beta (FIB). The major contribution of the overall
firm FIB rests on its ability to employ the full-information betas of the underlying underwriting
lines. Of interest here is the fact that these results form a foundation by which to examine the
efficient trade-offs in alternative return generating profiles that define the composition of the
underwriting portfolio.
Given the context of the property-liability ALM process as recently summarized by
Babble (2001) on the one hand, and Cummins and Phillips (2003) on the other, we establish an
objective for this research to extend the ALM of property-liability insurers to include the
simultaneous solution of a dual Markowitz (1952) mean-variance framework one on each side
of the firm s economic balance sheet. In this research we extend the contemporary application
of efficient asset-side risk mitigation to explicitly include the simultaneous efficient mitigation of
liability-side risk. The paper proceeds as follows. Section 2 presents the foundations of a
separable program that explicitly solves the nonlinear hierarchical goal program. Section 3
develops a nonlinear hierarchical goal ALM of a hypothetical, or generalized, property-liability
Nonlinear Heirachical Modeling for Insurers.
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firm. Because the purpose of this paper is illustrative, the model presented in this section does
not focus on a specific firm but is purposely generalized to meet the needs of any typical
property-liability insurer. Following the presentation of the model, solution results are discussed
in section 4. Section 5 is devoted to a summary of the findings.
2. A Separable Program for Nonlinear Hierarchical ALM
In goal programming it not always possible to satisfy all objectives simultaneously. Convex
goal programming is an appropriate and recognized optimization method by which to solve a
decision-model that is characterized by a defined organizational structure, heterogeneous
decision-making attributes, and hierarchical objectives. The nonlinear goal program applied to
the property-liability ALM presented in this paper is summarized as follows:
1
k
pp
Min Z h h
. .S T Ax Ih Ih b
, , 0x h h
where Z quantifies the k objectives (goals) so that an optimal solution to the linear program
associated with priority-one objectives is achieved prior to determining the optimal solution to
the linear program that defines priority-two objectives and so on. That is, in managerial
governance of the generalized property-liability insurer it is assumed that resource allocations
must be achieved in a prioritized sequence where Z1 > Z2 > > Zk. + and
- are constant terms
that indicate relative preference within each p-th goal; A is an m x n matrix of technological
coefficients created from the separable programming grid approximation; b is an m-component
vector of goal targets; h+ and h- are m-component column vectors that capture goal over- and
Nonlinear Heirachical Modeling for Insurers.
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under-achievement, respectively. Lastly, x is a n-component column vector of decision
variables.
The method proceeds by solving a sequence of modified linear programs (MLP) that are
consistent with separable programming constraints. The use of finite bounds on the decision
variables permits the development of a piecewise linear approximation for each nonlinear
function in the problem statement. To form a piecewise linear approximation using r line
segments, it is necessary to select 1r values of the scalar x over its range of 0 x u . By the
use of a grid of 1jr points for each variable jx over its range, the separable programming
problem in x becomes the following modified linear program in where an adjacency criterion
is imposed on the new decision variable kj by use of a restricted basis entry rule:
1 0: ( ) ( )j
kj
n r
kj kjj kMin f f x
Subject to:
1 0( ) ( ) , 1...,jn r
i kj kij ij k kjg g x b i m
01, 1,...,jr
kjkj n
0, 0,..., , 1,..., .kj jk r j n 2
2 Several researchers discuss the intricacies of separable methods. See Stefanov, S. M. (2001). "Convex Separable Minimization Subject to Bounded Variables." Computational Optimization and Applications: An International Journal
18(1): 27-48. for both theory and methods. For additional discussion, also see Drandell, M. (1977). "A Resource Association Model for Insurance Management Utilizing Goal Programming." The Journal of Risk and Insurance
44(June): 331-315., Feijoo, B. and R. R. Meyer (1988). "Piecewise-Linear Approximation Methods for Nonseparable Convex Optimization." Management Science
34(3): 411-419., and Fare, R., S. Grosskopf, et al. (1988). "On Piecewise Reference Technologies." Management Science
38(12): 1507-1511..
Nonlinear Heirachical Modeling for Insurers.
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Within the hierarchical goal program we define pC as the cost vector for goals at the p-th priority
level. The goal program proceeds to solve for the lexicographically smallest vector (c1x1, c2x2,
, cnxn). Given 1 | , 0x Ax b b the goal program proceeds by solving the first linear
program 1 1 1|LP Min C x x with optimal solution at x*. Then for each k-1 remaining x*, the
goal program iterates through all specified priority levels solving an LP at each step:
[ | ]p p pLP Min C x x , which implies that *1 1 1| , 1,2,..., 1p p p px x C x C x j p . For
parsimony, we note that alternative methods exist by which to formalize multi-criteria decision-
making in the treatment of resource allocation problems. For example, see Novikova and
Pospelova (2002) for an application to multicommodity networks.
3. The Hierarchical NLGP ALM for Property-Liability Insurers
The model presented here is forged from the generalized property-liability firm financial
statement as presented in table 1. The model is a one-period deterministic characterization of the
decision-making scenario. The notation is as follows. Beginning period values for asset
accounts are indicated by An , n = 1..N. Similarly, the beginning period value for each m-th
liability account is indicated by Lm for m =1..M. A buy or sell decision on n-th asset is
indicated by Bn and Sn , respectively. The rate used to make the buy and sell decision on n-th
asset is captured by rn .
<<< Insert Table 1>>>
Nonlinear Heirachical Modeling for Insurers.
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Insurance lines are defined in table 2. The model specification includes eight insurance
lines that are divided into property lines (P-lines) and non-property lines (non P-lines). The
distinction is necessary to capture the traditional regulatory structure. The premiums collected
on all insurance lines, both P-lines and non P-lines is captured by Pp , for p = 1..P lines. The
parameters needed to complete the specification of the model are detailed in table 3. These
parameters include both endogenously and exogenously determined characteristics of asset-
liability behavior.
<<< Insert Table 2>>>
<<< Insert Table 3>>>
3.1 Asset-Liability Efficiency Decisions
The property-liability company s firm manager faces two efficient diversification
problems. One is the efficient asset allocation of N investment portfolio securities. The other is
found on the liability side. It is the efficient balancing of operational risks incurred by the
underwriting function across M insurance lines. Equations (1) through (10) define the two
portfolio problems. Equations (1) through (5) state the MV asset allocation problem for
investment securities, while equations (6) through (10) define the MV diversification problem
for insurer underwriting activities. The portfolio optimization sub-models are formulated
following the specification of the approximating quadratic Sharpe (1963) diagonal model. The
Sharpe diagonal model simplifies the accounting for asset covariance by the inclusion of an N+1
asset. We invoke the Sharpe diagonal model to exploit a reduction in modeling characteristics
under the separable approximation created to represent the dual MV optimizations. Inputs to the
Nonlinear Heirachical Modeling for Insurers.
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Sharpe diagonal model are obtained by application of the single-index market model to the
individual traded assets: iS i i M iR a R , where ia is the component of security i's return
that is independent of the stock market's performance, MR
is the rate of return on the market
index, and i is a constant that measures the expected change in iSR given by a change in MR ,
and i is a random element with an expected value of zero and variance 2
i. In addition to 2
i,
which is the measure of unique (unsystematic) risk for the i-th security, the Sharpe diagonal
model also requires the variance of the market index, 2
MR , which is specified as the N+1 asset.3
The theoretical framework for estimating the systematic risk of non-traded assets held by
insurance firms was first presented by Fairley (1979). Not only did the Fairley results become
the foundation for rate application problems at the state level, but the theoretical underpinnings
of the model help to formalize the underwriting line diversification problem. Hill and
Modigliani (1987) presented a detailed case in the state of Massachusetts. More recent
contributions to the theory of underwriting line risk measurement are summarized in a review of
extensions by Lee and Cummins (1998) and Cummins and Phillips (2003).
3 A performance comparison of the diagonal and full-covariance model is reported by Cohen, K. J. and J. A. Pogue (1967). "An Empirical Evaluation of Alternative Selection Models." Journal of Business
40(2): 166-193. Representative extensions can be found in Frankfurter, G. M. (1976). "The Effect of Market Indexes on the Ex-post Performance of the Sharpe Portfolio Selection Model." The Journal of Finance
31: 949-955. For a summary of alternative computational methods, see Elton, E. J. and M. J. Gruber (1997). "Modern Portfolio Theory, 1950 to Date." Journal of Banking and Finance
1997: 1743-1759. More contemporary extensions that demonstrate alternative approaches is expemplified by Jobst, N. J., M. D. Horniman, et al. (2001). "Computational Aspects of Alternative Portfolio Selection Models in the Presence of Discrete Asset Choice Constraints." Quantitative Finace
1: 1-13. Finally, see Krokhmal, P., J. Palmquist, et al. (2001). "Portfolio Optimization with Conditional Value-At-Risk Objective and Constraints." Department of Industrial and Systems Engineering, University of Florida, Working Paper. for recent extensions that include value-at-risk specifications.
Nonlinear Heirachical Modeling for Insurers.
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3.1.1 Optimal Investment Account Management
Equation (1) and (2) state the unsystematic and systematic risk, respectively for N
investment securities. In (1) the N+1 security is the market index and 1
2
NS is its variability.
The systematic risk level of individual asset relative to the market index pS is captured in (2).
Equation (3) forces the portfolio to be fully invested (short-sales are not permitted). Equation (4)
is the goal constraint for the managerially determined portfolio return, pSR . Equation (5) is an
accounting restatement of return.
12
11
0i
N
S ii
x d
(1)
1i p
N
S i Si
x
(2)
1
1N
ii
x
(3)
4 41
i p
N
S i Si
r x d d R
(4)
1s i
N
r i Si
C x r
(5)
3.1.2 Optimal Insurance Line Diversification
Equations (6) through (10) state the MV diversification problem for the insurers M
underwriting lines. In this specification jc is the fraction issued in underwriting line j, and pIR is
the managerially determined desired return from the insurance underwriting portfolio.
12
61
0j
M
I ij
c d
(6)
Nonlinear Heirachical Modeling for Insurers.
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1
j p
M
I j Ij
c
(7)
1
1M
jj
c
(8)
9 91
j p
M
I j Ij
r c d d R
(9)
I jr j Ij
C c r
(10)
3.2 Premium Flows
Premium flows for j-th underwriting line are captured by jP . Equations (11) through
(18) are formulated to capture managerial goal setting. Total premiums written are defined
by 9P , in equation (19).
1 11 11 1 9P d d C P
(11)
2 12 12 2 9P d d C P
(12)
3 13 13 3 9P d d C P
(13)
4 14 14 4 9P d d C P
(14)
5 15 15 5 9P d d C P
(15)
6 16 16 6 9P d d C P
(16)
7 17 17 7 9P d d C P
(17)
8 18 18 8 9P d d C P
(18)
91
M
jj
P P
(19)
Nonlinear Heirachical Modeling for Insurers.
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3.3 NAIC Policy Effects
The National Association of Insurance Commissioners (NAIC) implemented the
Insurance Regulatory Information System (IRIS) to monitor the financial condition of property-
liability firms. The IRIS system is defined by eleven ratios categorized into four financial ratio
domains: a) overall, b) profitability, c) liquidity and d) reserves. The NAIC also identified
ranges that are considered indicative of a financially sound insurer. For the model developed
here, NAIC policy is partially interrogated by the specification of equations (20) and (21).
Equation (20) defines variable P10 to report total P-line premiums while equation (21) defines
P11 to capture total non P-line premium flows. The premium sub-totals calculated here are used
to facilitate an examination of the insurer s general financial health by the IRIS overall domain.
To sample this domain, the ALM model calculates the net premiums written to surplus ratio as
well as the change in writings ratio.
10 1 2 3 4 8P P P P P P
(20)
11 5 6 7P P P P
(21)
3.4 The ALM Balance Sheet
The accounting relationships that define the firm s balance sheet are specified in
equations (22) to (37). The ending period account values for the asset side of the balance sheet
are defined in equations (22) to (26). Ending period values represent the amount of beginning
period values that did not mature plus purchases less any sales of the asset. Account purchases
are limited to forecasted values as stated in equations (27) to (31). Equations (32) to (36) limit
the insurer s ability to engage in short-selling. The accounting identity is stated in equation (37).
Nonlinear Heirachical Modeling for Insurers.
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2 2 2 2(1 )A A a B S
(22)
3 3 3 3(1 )A A b B S
(23)
4 4 4 4(1 )A A c B S
(24)
5 5 5 5(1 )A A d B S
(25)
6 6 6 6(1 )A A e B S
(26)
2B f
(27)
3B g
(28)
4B h
(29)
5B k
(30)
6B l
(31)
2 2 (1 )S A a
(32)
3 3(1 )S A b
(33)
4 4 (1 )S A c
(34)
5 5 (1 )S A d
(35)
6 6 (1 )S A e
(36)
i ji j
A L
(37)
3.5 ALM Profitability Accounting
Equation (38) defines the policyholders' surplus account. For the model developed in this
research, all investment securities accounts are treated as perpetuities. Although this
Nonlinear Heirachical Modeling for Insurers.
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assumption is somewhat unrealistic, it does not interfere with the purpose of the model and its
exposition. The managerial goal associated with this account is to minimize under-achieving
accumulations to the capital account. Policyholders surplus is defined to be a function of
beginning period values plus the accrued effect owing to changes in premiums written. Added to
this are the planning period changes in balance sheet values. For example, the equation includes
revenue for the fraction of existing government securities that did not mature, r2
(1-a)A2
, plus
revenue associated with the purchase of new securities, r2B
2, plus (less) capital gains associated
with security sales, [r2
- (r2
/r2) + 1]S
2, where, again, investment securities are all treated as
perpetuities. Except for the investment asset account, the revenue structure presented above is
similarly applied to all remaining asset side accounts. Income from investment assets is
calculated by adjusting the desired return PSR by under (over) achievement 4d ( 4d ) as
applied to the end of period investment assets values, 6A . Finally, the account definition
concludes by recording accumulated losses from the fraction of the change in loss-reserves (1-
i ) that is charged to the policyholders' surplus account for each of the four loss-reserve
accounts. Stated differently, the parameter i is the fraction of the change in loss-reserve that is
carried forward.
10 37 10 10 11 2 2 2 20.62 0.69 (1 )L d L E P P r a A r A
22 2 3 3 3 3
21 1rr S r b A r Br
33 3 4 4 4 4
31 1rr S r c A r Br
44 4 5 5 5 5
41 1rr S r d A r Br
Nonlinear Heirachical Modeling for Insurers.
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55 5 4 4 6 1 5 5
51 1
PSrr S R d d A L Lr
2 6 6 3 7 7 4 8 81 1 1L L L L L L
(38)
3.6 Regulatory and Managerial Policy Effects
3.6.1 Liquidity
Equation (39) implements a basic regulatory requirement. This equation requires the
dollar investment in federal, state, municipal, and corporate bonds to equal total loss reserve for
all insurance lines with active premium flows.
2 3 4 39 39 2 3 4 5A A A d d L L L L
(39)
Equations (40) and (41) express the bounds on cash holdings as managerial goals. Taken
together, these two equations seek to produce an end-of-period cash account that falls between a
high and low dollar range. Both the upper- and lower-bound on cash holding are defined by
taking a percent of the total loss reserve. The upper bound is computed against loss reserves by
applying the upper bound percent, H . Similarly, the lower bound is computed by applying the
lower bound percent L .
1 40 40 2 3 4 5HA d d L L L L
(40)
1 41 41 2 3 4 5LA d d L L L L
(41)
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3.6.2 Loss Reserve Accounting
The property-liability insurer must account for the relationship between current and prior
year loss reserves for each insurance line against which premiums are written. Because the loss
settlement history differs across the j lines, the value assigned to the premium roll-off factor, j ,
is set to reflect this history. A small (large) value is more likely for a long (short) settlement
period. Additionally, end-of-period loss reserves also include the portion of premium income
earmarked for loss payments throughout the planning period, j . For some lines very little
premium income is ever used to pay for losses; hence, only a small fraction of premium income
in that line is needed to be set-aside in a reserve. Equations (42) through (45) define this
relationship for the loss reserve for underwriting activity in non P-lines, miscellaneous liability,
workers compensation liability and automobile liability insurance. We note that the economic
relationship defined here is the one-year change in writings to surplus ratio as defined by IRIS
policy.
2 42 1 2 1 10L d L P
(42)
3 43 2 3 2 6L d L P
(43)
4 44 3 4 3 7L d L P
(44)
5 45 4 5 4 5L d L P
(45)
3.6.3 Unearned Premium Reserve Accounting
Equations (46) - (49) detail the behavior of unearned premium reserve (UPR). The UPR
is the liability item that reflects premium revenues received for contractual coverage not yet fully
provided. The ending period UPR account is directly related to a fractional amount of the
Nonlinear Heirachical Modeling for Insurers.
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change in premium flows across two consecutive planning periods. Within the context of a one-
period model where premium flows are assumed to accrue evenly throughout the planning
period, a predetermined fraction of 0.5 with equal premium flows from one year to the next
would result in a constant UPR account as each dollar paid in losses would be replaced by
current premium writings.
6 46 6 10 100.5L d L P P
(46)
7 47 7 6 60.5L d L P P
(47)
8 48 8 5 50.5L d L P P
(48)
9 49 9 5 50.5L d L P P
(49)
3.6.4 Kenny Ratio
. During periods of remarkable profits the property-casualty industry could become
overly capitalized. The Kenny ratio is a well known industry specific approach that has been
favored by regulators to control an excessive accumulation of capital reserves. Generally, the
Kenny ratio is implemented to scale the premiums to surplus ratio at level of 2-1. Regulatory
review may be warranted when the ratio exceeds a level of 3-1. The Kenny ratio is implemented
across two equations. Equation (50) implements the upper bound ( U) of the Kenny dimension
as a constraint while equation (51) states the managerial goal ( L) for the relationship between
premiums and surplus.
9 50 10UP d L
(50)
9 51 51 10LP d d L
(51)
Nonlinear Heirachical Modeling for Insurers.
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3.7 Maximization of Firm Value
Maximization of firm value is controlled through equations (52) and (53). Maximization
of firm value is goal-directed by use of the policyholders' surplus account. In equation (52) the
goal value is set to an arbitrarily high value; a value so high that it will cause the NLGP model to
produce a solution that reflects the most efficient allocation of firm resources within the context
of all defined financial relationships.
3710 52 10L d
(52)
Similarly, the ALM confronts potential agent-theoretic conflicts that may arise in the
process of seeking efficient solutions that maximize overall firm value. The Jensen and
Meckling (1976) view of agency theory suggests that firm managers may act in their own best
interest when not monitored. This agency problem arises for property-liability insurers as they
consider the implications of generating underwriting production by either the independent
agency system or through the employment of firm supported exclusive dealing insurers tied
agents (see Regan (1999) for a comprehensive retrospective on the hypothesis). The use of
independent agents is known to result in higher expense ratios for insurers. But, because the tied
agent's revenue is produced by a single insurer, when a significant adverse experience with a
particular underwriting line occurs, the rational behavior for the tied agent is to demand either
higher compensation for writing riskier policies, or the right to direct new underwritings to less
complex lines. This dilemma may cause agents to assert managerial goals that are in conflict
with the constrained efficiency standards inherent in value maximization principle.
Equation (53) is implemented to control for the potential of agency conflict actions. In
its most basic expression, agency conflict would reflect the agent's desire to increase income
Nonlinear Heirachical Modeling for Insurers.
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through aggressive asset-side portfolio management while simultaneously limiting underwriting
combinations to less complex lines. The purpose of equation (53) is to utilize asset- and
liability-side MV sub-models to insulate the firm from agency conflict in the determination of
efficient investment asset and underwriting portfolio combinations.
53 53I sr r AC C d d R
(53)
3.8 The Hierarchical Objective Function
In the hierarchical goal programming model, it is the objective function that ties together
all goal and constraint equations. While the specification of the insurer ALM may be useful
across multiple individual firms within the industry, the model s goal hierarchy will certainly
differ at the firm level. The goal hierarchy modeled here is, like the ALM itself, a generalization
that represents the expression required to achieve efficient solutions to the embedded portfolio
problems while guided by the need to optimize firm value. Of course, more detailed and explicit
characterizations of firm goal hierarchy are possible in actual implementation of the model.
Equation (54) states the hierarchical objective function. The first priority (Z1), which
must be achieved before consideration of any lower level priorities, minimizes under-
achievement of two sub-objectives. Both sub-objectives have equal weight within this priority
level. Specifically, it is within this objective that we set the rate of return objectives for the two
MV portfolio diversification problems. The second priority (Z2) seeks to minimize over-
achievement in the portfolio risk dimension. When taken together, these two objectives operate
to fix the specified rate of return and then find the optimal allocation of investment-assets and
Nonlinear Heirachical Modeling for Insurers.
Page -21-
underwriting line premium flows that will best achieve the respective rate of return goal. The
third objective (Z3) captures the required shareholder maximization principle.
1 4 9 2 1 6 3 52:Min Z d d Z d d Z d
(54)
4. Application of the ALM to a Property-Liability Insurer
Alternative methods for solving the insurer ALM, including relevant forecasting
issues, are robustly discussed across Cummins and Nye (1981), Consiglio, et. al. (2002), Wang
and Yang (2002), and Yu, et. al. (2003). In this paper we introduce a scaled hypothetical
financial statement of a typical U.S. property-liability insurer as a means by which to explore the
contribution made by solving the dual MV across balance sheet ALM. To create the financial
statement of the hypothetical insurer we average reported balance sheet values across a sample
of U.S. headquartered property-liability insurers to obtain indicative individual account values.
Next, a common size balance sheet is derived to observe percent of asset/liability contribution
for each individual account. The hypothetical balance sheet is subsequently scaled to a $10,000
base based on the computed common size ratios. Beginning period values for the hypothetical
insurer financial statement are presented in table 4.
<<< Insert Table 4>>>
4.1 Data
Nonlinear Heirachical Modeling for Insurers.
Page -22-
The insurer ALM does not explicitly consider investment grade rankings for
individual investment account securities. The absence of this effect is managed by introducing
an upper bound constraint on the purchase of new assets (indicated by the maximum percent
increase). In the absence of such a constraint the ALM would simply take all of the liability
flows available without regard to the availability of interest earning assets. Finally, each asset
account specification includes a maturation parameter to capture the percentage of the asset that
matures (converts to cash) over the planning horizon.4 The upper bounds, forecast levels and
maturation parameters are presented in table 5.
<<< Insert Table 5>>>
Table 6 displays a sample of the forecasted dollar premium levels over growth (decay)
rates that vary from -25% to +100%. Associated interest rate parameters are presented in table
7. We note that variables with primes represent beginning period values. Conversely, variables
without primes capture the insurer s forecast of ending period rates that are expected to occur by
the end of the planning horizon.
<<< Insert Table 6, 7 >>>
Model data for policy parameters are presented in table 8. These values would be
observed directly from the firm s historical records or applicable regulatory statues. All
notations are as previously defined in section 3.
4 Under existing market definitions, some asset accounts may not mature (e.g., the investment assets account). In such cases, the maturation parameter is set to zero.
Nonlinear Heirachical Modeling for Insurers.
Page -23-
<<< Insert Table 8>>>
The data required to solve the dual Sharpe diagonal portfolio optimization problems is
presented in table 9. The table is divided into two sections. Data that specifies the
characteristics of each investment asset may be found in the left-most section of the table. This
data includes each securities expected rate of return, its systematic risk coefficient (beta), and a
measure of unsystematic risk ( 2). Parallel structure follows in the presentation of the risk and
return measures for the underwriting lines.
<<< Insert Table 9>>>
4.2 Representative ALM Solutions
Comparative ending- and beginning-period balance sheets produced by solving the model
under different economic scenarios are presented in tables 10 and 11, respectively. To obtain
these results, we varied two policy parameters one on each side of the balance sheet. On the
asset side of the balance sheet we vary the agency theoretic required rate of return, equation (53).
On the liability side of the balance sheet we explore alternative growth rate scenarios for
insurance underwriting premiums. For premium growth (decay), we started the simulation
process at extreme values. For example, for an insurer operating under a forecast for a 98
percent decline in premium flows, the model s solution finds that seeking a rate of return of one-
percent from the across balance sheet portfolio activities produces minimal total asset growth to
$10,491. While it is possible to generate any number of economic scenarios, we focused
substantial effort on solutions characterized by an eight percent growth rate in premiums.
Holding this policy dimension constant, we then allowed the agency rate of return that binds the
Nonlinear Heirachical Modeling for Insurers.
Page -24-
dual MV portfolio problems to vary between 8 and 50 percent (8-, 12-, 15-, 18-, and 50-percent
are shown in the tables).
<<< Insert Table 10, 11>>>
It is immediately obvious that the property-liability firm s total asset growth is impacted
by hierarchical goal resolution within the simultaneous risk mitigation strategies defined on both
sides of the balance sheet. Stated differently, the model s solution confirms the conventional
wisdom that an insurer s scale of operation is dependent upon the change in premium
underwritings. However, this wisdom is challenged in the face of excessive risk taking on the
asset side of the balance sheet as such activity can retard the growth in total assets. The model
exemplifies this fact as the decay in premium writings abates from a negative 98 percent to a
negative 25 percent. Total assets show growth to $11,697. This positive trend in total asset
growth continues as premium flows are subjected to higher and positive growth rates. However,
when we halt the growth rate of premiums at 8 percent and hold it constant, we note that total
asset growth stalls when management sets required asset returns between 12- and 18-percent. At
a 50 percent required rate of return the insurer is forced into ill-logical financial statement
combinations. That is, at this unrealistically high rate of return, the insurer simply accumulates
earnings in the cash account as forecasted purchase levels for securities and investment assets are
already at their maximum investment grade level. Upon first review, this may seem to be an
idiosyncrasy of the model. However, this characterization could be indicative of agency conflict
where tied agents attempt to increase overall firm returns by assuming excessive asset side
investment risk as a means by which to offset their desire to reduce new underwriting flows in
risky (but high yielding) insurance lines.
Nonlinear Heirachical Modeling for Insurers.
Page -25-
Returning to the plausible specification of 8 percent as a growth rate for premium
underwritings and as a required rate of return expected from the across balance sheet MV
portfolios, we present the optimal allocation of the investment asset and underwriting portfolio in
table 12. To accommodate the coarseness of the separable programming grid, for expository
purposes only a two percent minimum allocation constraint was added to the investment account
specification. By permitting the agent theoretic required rate of return to vary the efficient set is
produced and displayed in figure 1. As with the findings presented for the 8 percent level, any
point on the efficient set represents the efficient combination to the simultaneously obtained
across balance sheet portfolio problems. Stated differently, as the insurer interrogates alternative
agent theoretic expected returns, the ALM produces the optimal combination of investment
assets to hold as well as the optimal underwriting combinations to seek over the planning
horizon. The second efficient set shown in figure 1 is dominated by the one obtained from
solving the insurer ALM. The dominated efficient set, shown for visual reference only, provides
ancillary evidence that the simultaneous solution of the dual MV problem increases overall
insurer financial solvency.
<<< Insert Table 12 >>>
<<< Insert Figure 1 >>>
A closer examination of the 8 percent solution reveals an ending period value of $602.80
for the investment asset account (see table 10). This amount is optimally allocated at 13.47- and
72.53- percent between asset 2 and 7, respectively. All other securities enter at the 2-percent
structural constraint level. The return generated by the asset-side diversification strategy is 6.59
percent with a corresponding risk (standard deviation) of 4.19 percent. By contrast, the rate of
Nonlinear Heirachical Modeling for Insurers.
Page -26-
return from the insurance underwriting function is 1.30 percent. The ranked diversification path
for underwriting calls for the insurer to focus on: automobile liability, fire, homeowners
liability, commercial multiperil, and allied fire liability. All remaining underwriting lines enter
at a contribution level under 5 percent of the underwriting portfolio. When added together, the
solution produced an across balance sheet return of 7.90 percent. The difference between the
target 8 percent return and the actual results is attributed to rounding error attributable to the
coarse two-grid point approximation. Figure 1 also shows three points labeled B, K, and M.
These points represent the risk-return relationships of the insurance portfolios alone. Stated
differently, without the ability to invest in asset-side equity investments, property-liability firms
would generate risk-return profiles at these three interior points. The dominance principle
demonstrated by solving the across balance sheet efficient diversification problems provides
normative support for the full balance sheet hypothesis as advanced by Babbel (2001)
4.3 Premium Volume
At the 8% growth level, the model does not take all of the premiums that were forecasted.
This is directly related to the structural link between premium income and the optimal
underwriting combination. The goal over (under) achievement for the insurer underwriting lines
is reported in table 13 (a and b). Negative values suggest a failure to take premiums in an
amount equal to the optimal contribution. By contrast, positive values in this table report an
over-achievement of the optimal flow goal. When the forecasted change in premium flows is
negative, the insurer always takes the entire available forecast. However, as flow forecast
changes to positive values we can again observe the conservative nature of the ALM at work.
There is an increasing divergence between the ability of the insurer to employ new premium
Nonlinear Heirachical Modeling for Insurers.
Page -27-
volume effectively at growth rates that range from 4 percent up to 12 percent. Despite a small
narrowing (or elimination) of the divergence above 12 percent, at extremely high premium
growth rates (50- and 100-percent, respectively), the insurer accepts all forecasted premium
volume. However, as previously noted, this action is irrational insurer behavior as it leads to
distorted balance sheet allocations.
<<< Insert Table 13a and 13b >>>
4.4 Financial Policy and Regulatory Objectives
Under the 8 percent solution, cash holdings meet the bounds established by equations
(39) through (41). All loss-reserve and unearned premium reserve accounting are also met.
Importantly, the ALM specification lends itself to important ratio calculations. The insurer
solvency ratios produced under this scenario are presented in table 14. The impact of the
optimizing process is evident. For example, the Kenny ratio stays at a relative conservative level
reaching a value of 1.35. The ratio 1-year change in premium writings to policyholders surplus
shows a modest decline. This too is a reflection of the conservative solution generated by the
ALM when premium volume grows at the moderate rate of 8 percent per period. While the
conservative trend is reflected across the entire ratio analysis it is clear that the ALM produced
desired profitability while simultaneously increasing the overall efficiency of the generalized
property-liability insurer.
<<< Insert Table 14 >>>
Nonlinear Heirachical Modeling for Insurers.
Page -28-
4.5 Other Considerations
A basic premise uncovered by the model solution process suggests that the property-
liability insurer should avoid the sale of assets to raise liquidity. Instead, management should
focus on generating cash flow through its underwriting activity. Further, in the case where
underwriting activity is excessive and it is no longer possible to invest cash flow in traditional
investment grade assets, then management should search out "other assets" as well as hold cash
rather than reject new insurance business. However, as shown from alternative solutions of the
model, this latter scenario should be avoided due to the unacceptable balance sheet ending period
allocations. In summary, the model strategically and conservatively models efficient responses
to realistic economic scenarios while it sheds new light on the consequences from potentially
irrational insurer behavior that could arise owing to agency theoretic conflicts.
5. Summary and Conclusion
This research paper examined the performance of a one-period ALM for a hypothetical
property-liability insurer. The model extended prior model building efforts by explicitly
incorporating the extensions suggested by Babbel (2001) on the one hand, and Cummins and
Phillips (2003) on the other. The ALM model introduced in this research incorporated a dual
MV optimization problem that encompassed both sides of the insurer balance sheet. The asset
side MV diversification problem is well-known. Recent extensions to the liability side risk
measurement in the property-liability industry led to the model extension that permitted the
simultaneous incorporation of the second MV specification. Relying upon hypothetical
underwriting risk coefficients, coefficients that are easily generated by methods discussed in the
extant literature, the nonlinear hierarchical ALM produced both a simultaneous optimization of
Nonlinear Heirachical Modeling for Insurers.
Page -29-
the firm s across balance sheet management portfolio problems as well as a goal satisfying
solution that balanced the potential for agency conflict. Despite the need to create a linear
approximation of the nonlinear problem, the results produced from solving the model proved to
be consistent with normative applications in MV theory while clearly demonstrating the
usefulness of incorporating the MV problem with the specification of the firm s goal hierarchy.
The robustness of the current ALM solution argues well for a model extension that would
incorporate more complex economic environments that are best modeled by stochastic
relationships. Additionally, the model as currently configured ignores tax effects, derivative
instruments, timing decisions, and a more detailed profit-loss functional definition. The latter
point is of keen interest as a detailed profit-loss statement would permit a greater focus on
important ratios that are not fully enumerated in the current model (e.g., the combined ratio).
Finally, one additional aspect that was not explored in this paper is a model enhancement that
would permit the generation of an efficiency set of alternate insurer balance sheets. Such an
extension would allow insurers to explore the price of risk associated with the trade-off between
investment and underwriting opportunities. Regulators, by contrast, would be able to observe
useful information about the firm s ability to mediate risky managerial decisions and risky
economic environments.
Nonlinear Heirachical Modeling for Insurers.
Page -30-
Table 1. Generalized Property-Liability Firm Financial Statement
Assets Beginning Period Values
Purchase Variable
Sale Variable
Rate
Parameter
Liabilities Beginning
Period Values
Cash A1
Liabilities & Other L1
Federal Govt. Sec. A2
B2 S2 r2 Loss Reserves: P Lines L2
State & Local Sec. A3
B3 S3 r3 Loss Reserves: Misc. L3
Corp. Bonds A4
B4 S4 r4 Loss Reserves: Workers Comp. L4
Preferred Stock A5
B5 S5 r5 Loss Reserves: Auto-Bodily Injury L5
Investment Assets A6
B6 S6 r6 Unfunded Premiums: P Lines L6
Other Assets A7
B7 S7 r7 Unfunded Premiums: Misc. L7
Unfunded Prem. Res: Workers Comp. L8
Unfunded Prem. Res: Auto-Bodily Injury L9
Policyholders Surplus L10
Nonlinear Heirachical Modeling for Insurers.
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Table 2. Insurance Lines and their Premium
Insurance Line Property Premium
Non-Property Premium
Fire P1
Allied Fire Liability P2
Homeowners Liability P3
Commercial-Multi Peril P4
Automobile Liability P5
Miscellaneous Liability P6
Workers Compensation P7
Automobile Physical Damage P8
Nonlinear Heirachical Modeling for Insurers.
Page -32-
Table 3. Modeling Parameters and Variables
Parameter Variable Description
N Number of investment securities
M Number of insurance lines
iS
Unsystematic risk for the i-th investment security (S)
jI
Unsystematic risk for the j-th insurance line (I)
iSr
Rate of return on the i-th investment security
jIr
Rate of return on the j-th insurance line
iS
Beta for the I-th investment security
jI
Beta for the j-th insurance line
ix
Fraction invested in the i-th security
jc
Fraction invested in the j-th insurance line
a Maturation fraction of federal government securities
b Maturation fraction of state and local obligations
c Maturation fraction of corporate bonds
d Maturation fraction of preferred stock
e Maturation fraction of investment assets
f Purchase forecast of federal government securities
g Purchase forecast of state and local obligations
h Purchase forecast of corporate bonds
k Purchase forecast of preferred stock
l Purchase forecast of investment assets
i
Change in policyholders surplus
j
The fraction of loss reserve of the j-th insurance line carried over to the next year
j
The fraction of premiums kept as reserve for the j-th insurance line
Kenny ratio parameter (see definition in sec 3.9.3)
Bounded Liquidity parameter (see definition in sec 3.9.1)
p Subscript referring to the portfolio
Nonlinear Heirachical Modeling for Insurers.
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Table 4. Beginning Period Values
Assets Value
Liabilities Value
Cash 947
Liabilities & Other 958
Federal Govt. Sec. 1,043
Loss Reserves: P Lines 2,299
State & Local Sec. 4,187
Loss Reserves: Misc. 584
Corp. Bonds 1,261
Loss Reserves: Workers Comp. 638
Preferred Stock 378
Loss Reserves: Auto-Bodily Injury 1,132
Investment Assets 1,507
Unfunded Premiums: P Lines 1,015
Other Assets 677
Unfunded Premiums: Misc. 169
Unfunded Prem. Res: Workers Comp. 285
Unfunded Prem. Res: Auto-Bodily Injury 479
Policyholders Surplus 2,441
TOTAL $10,000
TOTAL $10,000
Table 5. Asset / Liability Forecast with Corresponding Maturation
Asset Category Upper Bound of Percent Increase
Forecast Parameter Maturation Parameter
Federal Govt. Sec. 30% f = 1,355.90 a = 0.80
State & Local Sec. 15% g = 4,815.05 b = 0.05
Corp. Bonds 50% h = 630.50 c = 0.00
Preferred Stock 30% k = 113.40 d = 0.00
Investment Assets 40% l = 602.80 e = 0.00
Nonlinear Heirachical Modeling for Insurers.
Page -34-
Table 6. Premium Dollar Values: Beginning Period and Various Forecast Levels
Insurance Lines Beginning Period
-25% 25% 30% 50% 100%
Fire 461.30 345.98
576.63 599.69 691.95 922.60
Allied Fire Liability 117.50 88.13
146.88 152.75 176.25 235.00
Homeowners Liability 277.70 208.27
347.12 361.01 416.55 555.40
Commercial-Multi Peril 243.00 182.25
303.75 315.90 364.50 486.00
Automobile Liability 433.20 324.90
541.50 563.16 649.80 866.40
Miscellaneous Liability 37.90 28.43
47.38 49.27 56.85 75.80
Workers Compensation 41.40 31.05
51.75 53.82 62.10 82.80
Auto. Physical Damage 77.00 57.75
96.25 100.10 115.50 154.00
Table 7. Interest Rate Parameters
Beginning Period
Rate Planning Period
Rate
r2
0.060 r2 0.070
r3
0.050 r3 0.054
r4
0.070 r4 0.073
r5
0.065 r5 0.069
Table 8. Policy Parameters
Parameter Value
i
1.47
1
0.15
2
1.54
3
1.54
4
1.47
i
0.20
H
4.00
L
2.00
H
0.15
L
0.10
Nonlinear Heirachical Modeling for Insurers.
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Table 9. Portfolio Model Data
Security E(r) Beta
2 Insurance Line E(r) Beta
2
Sec_001 0.064
0.896
0.0266
Fire 0.010
0.850
0.0013
Sec_002 0.062
0.468
0.0072
Allied Fire Liability 0.050
1.895
0.0380
Sec_003 0.146
1.110
0.0441
Homeowners Liability -0.001
0.350
0.0270
Sec_004 0.173
1.361
0.0292
Commercial-Multi Peril 0.068
1.361
0.0901
Sec_005 0.198
1.273
0.0756
Automobile Liability -0.010
0.857
0.0035
Sec_006 0.056
0.590
0.0310
Miscellaneous Liability -0.014
1.313
0.1500
Sec_007 0.128
0.527
0.0207
Workers Compensation 0.028
0.981
0.0091
Sec_008 0.190
1.733
0.0384
Auto. Physical Damage 0.004
0.568
0.0280
Sec_009 0.116
1.041
0.0437
Market Index
0.0397
Insurance Industry Index
0.0800
Nonlinear Heirachical Modeling for Insurers.
Page -36-
Table 10. Projected Growth Rates and Optimal Asset Allocation Strategies
Projected Premium Growth Rates
E(r) Total Portfolio
Cash Federal Govt.
Securities
State & Local Securities
Corporate Bonds
Preferred Stock
Inv. Assets
Other Assets
Total Assets
-98.00%
1.00% 944.20 1355.90 4875.18 1891.50 113.40 602.80 708.15 10491.14
-25.00%
1.00% 1052.74 1355.90 6521.71 1261.00 113.40 602.80 789.55 11697.10
0.05%
18.00% 1313.62 1355.90 7955.30 1891.50 491.40 602.80 985.21 14595.73
4.00%
18.00% 1496.88 1564.50 7955.30 1891.50 491.40 3109.80 1122.66 16632.05
8.00%
8.00% 1093.06 1355.90 6268.70 1891.50 113.40 602.80 819.80 12145.17
8.00%
12.00% 1156.66 0.00 7955.30 1891.50 378.00 602.80 867.49 12851.75
8.00%
15.00% 1156.66 0.00 7955.30 1891.50 378.00 602.80 867.49 12851.75
8.00%
18.00% 1156.66 0.00 7955.30 1891.50 378.00 602.80 867.49 12851.49
8.00%
50.00% 1496.88 1564.50 7955.30 1891.50 491.40 2109.80 1122.66 16632.05
15.00%
18.00% 1140.83 208.60 7955.30 630.50 378.00 1507.00 855.62 12675.62
25.00%
18.00% 1496.88 1564.50 7955.30 1891.50 491.40 2109.80 1122.66 16632.05
30.00%
18.00% 1117.11 1355.90 6115.78 1891.50 491.40 602.80 837.83 12412.32
50.00%
18.00% 1156.96 1355.90 6866.78 1891.50 113.40 602.80 867.72 12855.06
100.0% 18.00% 1228.83 1355.90 7539.62 1891.50 113.40 602.80 921.62 13653.68
Nonlinear Heirachical Modeling for Insurers.
Page -37-
Table 11. Projected Growth Rates and Optimal Liability Allocation Strategies
Projected Premium Growth Rates
E(r) Total Portfolio
Liabilities and Other
Loss Reserve P Lines
Loss Reserve Misc.
Loss Reserve Workers Comp
Loss Reserve Auto B.I.
Un-earned Premium P
Lines
Un-earned Premium
Misc.
Un-earned Premium Workers Comp
Un-earned Premium Auto Bodily Injury
Policy-holders Surplus
-98.00% 1.00% 996.66 2302.53 585.17 639.28 1134.26 1615.02 188.33 306.11 521.83 2201.95
-25.00% 1.00% 1111.22 2431.36 627.77 685.82 1216.89 2044.44 202.16 321.23 679.95 2376.26
0.05% 18.00% 1386.59 2475.52 642.40 701.79 1245.25 2191.65 206.91 326.41 734.21 4685.01
4.00% 18.00% 1580.04 2479.00 644.70 704.31 1249.72 2203.27 207.66 327.23 742.76 6493.36
8.00% 8.00% 1153.79 2482.53 647.04 706.86 1254.25 2215.03 208.42 328.06 751.43 2397.77
8.00% 12.00% 1730.16 2482.53 647.04 706.86 1254.25 2215.03 208.42 328.06 751.43 2527.99
8.00% 15.00% 1730.16 2482.53 647.04 706.86 1254.25 2215.03 208.42 328.06 751.43 2527.99
8.00% 18.00% 1730.16 2482.53 647.04 706.86 1254.25 2215.03 208.42 328.06 751.43 2527.99
8.00% 50.00% 1580.04 2482.53 647.04 706.86 1254.25 2215.03 208.42 328.06 741.18 6468.65
15.00% 18.00% 1327.57 2501.95 651.12 711.32 1262.17 2279.74 209.74 329.51 766.59 2636.15
25.00% 18.00% 1580.04 2506.54 656.96 717.69 1273.49 2295.04 211.64 331.58 788.25 6270.82
30.00% 18.00% 1179.17 2514.84 659.88 720.88 1279.15 2322.71 212.59 332.61 760.64 2429.86
50.00% 18.00% 1221.23 2563.71 671.55 733.63 1301.79 2485.63 216.37 336.75 842.40 2481.99
100.0% 18.00% 1297.10 2651.95 700.73 765.51 1358.38 2779.75 225.85 347.10 950.70 2576.60
Nonlinear Heirachical Modeling for Insurers.
Page -38-
Table 12. Solution: Optimal Portfolio Allocations
Security xi Insurance Line Cj
Sec_001
2.00%
Fire 23.19%
Sec_002
13.47%
Allied Fire Liability 6.96%
Sec_003
2.00%
Homeowners Liability 16.44%
Sec_004
2.00%
Commercial-Multi Peril 14.39%
Sec_005
2.00%
Automobile Liability 29.77%
Sec_006
2.00%
Miscellaneous Liability 2.24%
Sec_007
72.53%
Workers Compensation 2.45%
Sec_008
2.00%
Auto. Physical Damage 4.56%
Sec_009
2.00%
Rp 6.59%
Rp 1.30%
p 4.19%
p 9.18%
Figure 1: Efficient Frontiers
Rat
e of
Ret
urn
Variance
R
ate
of R
etur
n
Nonlinear Heirachical Modeling for Insurers.
Page -39-
Table 13a. Premium Volume Goal Over (-under) Achievement
Growth -98% -25% 0.05% 4% 8%
Fire 3.67 137.70 183.99 167.41
151.23
Allied Fire -2.51 24.79 -125.56 -130.52
-135.54
Homeowners -3.11 -116.62 -155.87 -161.72
-167.94
Coml MP 4.10 153.83 205.20 213.30
221.51
Auto Liab 7.84 293.85 392.00 407.47
423.14
Misc. Liab -0.78 -29.32 -39.12 -40.66
-42.23
Worker Comp 0.67 30.90 41.32 42.95
44.61
Auto PD 1.54 57.75 77.04 80.08
83.16
Forecast 33.78 1266.75 33.78 1756.56
1824.12
Actual 33.78 1266.75 33.78 1733.03
1777.06
Table 13b. Premium Volume Goal Over (-under) Achievement (cont.)
Growth 15% 25% 30% 50% 100%
Fire 333.30 142.46 148.16 275.40 367.20
Allied Fire -144.32 -156.87 -163.15 -188.25 -251.00
Homeowners -178.82 -194.37 -125.27 -68.26 -311.00
Coml MP 235.87 256.38 266.63 307.65 410.20
Auto Liab 450.57 489.75 432.46 587.70 783.60
Misc. Liab -44.96 -48.87 -50.83 -58.65 -78.20
Worker Comp 47.51 51.64 53.71 61.99 82.70
Auto PD 88.55 96.25 100.10 115.50 154.00
Forecast 1942.35 2111.25 2195.70 2533.50 3378.00
Actual 1942.35 2024.21 2028.30 2533.50 3378.00
Nonlinear Heirachical Modeling for Insurers.
Page -40-
Table 14. Financial Ratios
Ratio Ending Period
Beginning Period
Total Premiums to Surplus 0.74 0.69
Liabilities to Liquid Assets 0.47 0.48
Loss Reserves to Surplus 1.60 1.44
Allied Fire to Fire Lines 0.28 0.25
1 Year Change in Writings to Policyholders Surplus 0.05 0.08
Kenny Ratio 1.35 1.31
Nonlinear Heirachical Modeling for Insurers.
Page -41-
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BarNiv, R. and J. B. McDonald (1992). "Identifying Financial Distress in the Insurance Industry: A Synthesis of Methodological and Empirical Issues." Journal of Risk and Insurance
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