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This white paper by Louise Francis discusses various methods for estimating fair values of assets and liabilities within actuarial science. It emphasizes that fair value equals market value for assets, while for liabilities, since market values are typically not available, fair value is calculated using present value of liabilities at risk-free rates, adjusted for risk loads. The paper details methods such as CAPM, IRR, and other risk adjusted discount techniques, while also addressing the perspectives of finance and actuarial theories in risk estimation, underscoring the significance of non-diversifiable risks.
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CAS Fair Value Task Force White Paper Methods of Estimation Louise Francis Francis Analytics and Actuarial Data Mining, Inc. louise_francis@msn.com
Methods Section • Discusses how fair values are estimated • For Assets : Fair Value = Market Value • For Liabilities: Market Value generally not available • Fair Value = PV(Liabilities)@rf • + risk load • + other adjustments
Methods Section • PV(Liabilities)@rf considered straightforward to estimate using standard actuarial procedures • This section focuses on methods of computing risk loads
The Methods • CAPM based methods • IRR approach • Single Period RAD • Methods that use historical underwriting data • Methods using probability distributions • Using reinsurance data • Direct Estimation Method • Transformed Distributions • Rules of thumb • Other
Two Major Paradigms • Finance Perspective • Only non diversifiable risk included in risk load • Non diversifiable risk used in risk load is systematic risk • Actuarial Perspective • Diversifiable risk matters • Non diversifiable risk used in risk load is parameter risk
Method 1: CAPM Based • CAPM for assets: • rA = rf + βA (rM – rf) • CAPM for liabilities • rL = rf + βL (rM – rf) • βA is positive, βL is negative
Method 1: CAPM Based • A number of different ways to estimate βL • Compute βe and βA for insurance companies. Get βL by subtraction. • Regress accounting underwriting profitability data on stock market index • Regress accounting underwriting profitability data by line on industry all lines profitability
Method 1: CAPM • Method is controversial • Estimates of βL very sensitive to estimates of βA because of leverage • Accounting data biased • CAPM under attack in Finance literature • See Kozik, PCAS, 1994
Method 2: IRR • A pricing based method • Uses the IRR pricing method to back into a risk adjusted discount rate • Internal rate of return on • capital contributions and withdrawals equals required rate of return
Method 2: IRR • Requires a surplus allocation • Requires an estimate of (target) ROE • Assumes risk load on reserves lies on a continuum with risk load used in pricing
Method : Risk Adjusted Discount Method • A pricing based method • Uses relationship between required ROE, expected investment return, income tax rate and capital to find risk adjusted discount rate
Method 3: Risk Adjusted Discount Method Example • Leverage (S/L) .5 • ROE .13 • E(rI) .07 • E(rF) .06 • E(t) 0 • E(L) $100 • Risk Adj = (S/L)*(ROE - E(rI)) +E(rF) -E(rI) = .5* (.13 - .07) + .06 - .07 = .02
Method 4: Based on Underwriting Data • Bases risk adjustment on long term averages of profitability observed in underwriting data. • Method first published by Butsic (1988) to compute risk adjusted discount rates • Uses industry wide data, possibly for all lines • Unless data for very long periods is used, results could be unstable
Method 4: Based on Underwriting Data • c = (1+rF)-u – e(1+rF)-w – l(1+rA)-t • c is ratio of PV(profit) to premium • rF is risk free rate, rA is risk adjusted rate • e is expense ratio • l is loss and LAE ratio • u is duration of premium, w is duration of expenses, t is duration of liabilities • Ratio c to average discounted losses to get risk adjustment: RA = (1+rF)c/Vm • Vm = PV(.5*(1+f)*L)), f is % losses outstanding at end of year
Method 5: Distribution Based Risk Loads • Three classical actuarial risk load formulas • Risk load = λ (sd Loss) • Risk load = λ (var Loss) • U(Equity) = E[U(Equity + Premium - Loss)] • A recent actuarial risk load formula • Risk Load = Surplus Requirement • Surplus requirement from Expected Policyholder Deficit calculation
Method 5: Distribution Based Risk Loads • All four formulas require a probability distribution for aggregate losses • Simulation and Heckman-Meyers are common methods for deriving probability distribution • Probability distribution includes process and parameter risk • Risk load may not be value additive • Typically gives a risk load that is applied to PV(liabilities), not an adjustment to discount rate.
Method 5: Distribution Based Methods • The aggregate losses displayed in the graph have a mean of $4.7M, and sd of $1.4M and a variance of 1.9*1012. • A variance based risk load might have a λ of 10-7 • Risk load = 10-7*1.9*10-12=190,000
Method 5: Distribution Based Methods • Standard deviation based risk loads often use the sd to derive a theoretical surplus: • Surplus (S) = z.999*sd = 3.1* 1.4M = 4,340,000 • Philbrick’s method for converting this into a risk load: • Risk Margin=(ROE-rf)/(1+ROE)*S • If ROE = .13 and rf =.06 • Risk Margin =(.13-.06)/1.13*4,340,000=230,442
Method 5: Distribution Based Methods • This result is about 5% of liabilities. • The risk margin might be 5% of liabilities discounted at the risk free rate • A more complicated formula for liabilities paying out over several years • RM=Σ(ROE-rf)St/(1+ROE)t
Method 6: Using the Reinsurance Market • Reinsurance surveys • Conceptually similar to PCS Cat options • Extrapolate from companies’ own reinsurance program • Compare price charged by reinsurers to PV(liabilities)@rF to get risk load • Might need to make adjustments for riskiness of layers
Method 7: Direct Estimation • Directly uses market values of companies’ equity and assets to derive market value of liabilities • MV(Liabilities) = MV(Assets) – MV(Equity) • Ronn-Verma method used to compute MV(Equity)
Method 8: Distribution Transform Method • Based on transforming aggregate probability distribution • Simple example: x -> kx • Where k>1
Method 8: Distribution Transform Method • Power transform • S*(x)->S(x)p • S(x) is survival distribution of x ,(1 – F(x)) • p is between 0 and 1 • The tail probabilities increase • Mean also increases • Choice of p depends on riskiness of business
Method 8: Distribution Transform Method Applied to Lognormal Aggregate Probability Distribution Transform distribution with p of .75. Mean 10% higher than original mean.
Method 8: Distribution Transform Method • Let F(x)=1-(b/(b+x))q, S(x)=b/(b+x)q • S*(x) = (b/(b+x))qp • E(x) =b/(q-1) • E*(x)=b/(qp-1) • ILF*(L)=1-(b/(b+L))qp-1/(1-b/(b+100000))(qp-1)
Method 8: Distribution Transform Method b=$5,000 q=1.6 p=.95 • E(x)=5,000/.6=8,333 • E*(x) = 5,000/.52 = 9,615, about 15% higher than E(x) • ILF(1M) =1.142 • ILF*(1M)=1.179
Method 9: Rules of Thumb • In some situations there may not be adequate data or other resources to develop risk loads from scratch • Rules of thumb may provide a quick and dirty by adequate approach • Might require an industry committee to develop the rules
Method 9: Rules of Thumb • Examples • Compute the risk adjusted discount rate by subtracting 3% from the risk free rate • The risk load should be 10% of the present value of liabilities in the General Liability line and 5% of liabilities in the Homeowners line
Method 10: Other • Intended to account for new methods which are developed and reasonable methods not covered here • Risk margin should be positive