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Risk Transfer Testing of Reinsurance Contracts. A Summary of the Report by the CAS Research Working Party on Risk Transfer Testing CAS Ratemaking Meeting March 2008 David L. Ruhm, FCAS. Background.
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Risk Transfer Testing of Reinsurance Contracts A Summary of the Report by the CAS Research Working Party on Risk Transfer Testing CAS Ratemaking Meeting March 2008 David L. Ruhm, FCAS
Background • AAA Committee on Property and Liability Financial Reporting (COPLFR) requested input on risk transfer testing, 2005 • CAS formed Working Party on Risk Transfer Testing to respond to AAA request (Michael Wacek, chair) • Working Party Report issued, Summer 2005 • More developments since – see AAA and NAIC websites
Background, continued • Paper on Working Party Report published in Variance, Spring 2007 (Ruhm & Brehm) • Paper briefly describes 2 risk measurement methods in Working Party Report: • Expected reinsurer deficit (ERD) • Right-tailed deviation (RTD) • Paper also describes risk coverage ratio (RCR) method, which is related to ERD
Scopes of WP report, Variance paper • Working Party took accounting rules as given • Merits of accounting rules not debated • Focus was on risk transfer testing methods • Variance paper provides a brief summary of some key material from WP Report • Also includes risk coverage ratio (RCR) • Interested parties should read the full WP Report
Risk measurement: Practical uses • Better risk control, including ERM context • “You can manage only what you can measure” • Pricing and strategic planning • Ensure expected profit is adequate compensation for amount of risk assumed • Risk-based capital allocation • Capital ~ risk adequate price ~ adequate ROC
Risk measurement: Accounting • If a contract “transfers risk” it can receive insurance accounting treatment • If not, premiums are treated as “deposits” and net results are amortized into earnings over time • Insurance accounting is often preferred • Risk transfer requirements are similar for GAAP and Stat • GAAP: FAS 113 • Stat: SSAP 62
SSAP 62 highlights • Reinsurer must assume “significant” insurance risk • Requires non-remote probability of significant variation in amount & timing of payments by reinsurer • “Reasonably possible” that reinsurer may realize a “significant” loss • Based on NPV of all cash flows between ceding & assuming companies under reasonably possible outcomes (emphasis added).
WP proposed testing framework • Three-step process • 1. Determine if contract transfers “substantially all the risk” – if so, stop. • Assumed downside essentially same as cedant’s original • 2. Determine whether or not risk transfer is “reasonably self-evident” – if so, stop. • E.g., cat x/s, x/s w/no loss sensitive features • 3. Calculate recommended risk metrics and compare values to critical threshold values.
Expected reinsurer deficit (ERD) • Uses probability distribution of net economic outcomes (NPV of cash flows) • Critical point = $0 gain = economic breakeven • Formula: ERD = pT / P • p = probability of net loss • T = average conditional loss severity • P = expected premium
Expected reinsurer deficit (ERD) • Concepts inherent in ERD: • “Risk zone” is area in distribution where economic loss exists in terms of negative NPV • Risk = loss frequency x average loss severity • Base in denominator = expected premium, measuring risk per $1 premium
ERD example • Simple example of ERD calculation • Aggregate excess $250m excess of $500m • Settlement 1 year after inception • Investment yield = 4.00% (1-yr risk-free rate available at inception) • Premium = $10m at inception
ERD example • Loss distribution (dollars in $000) Ceded lossProbabilityNPV(gain) $ 0 96% $ 10,000 $ 50,000 2% ($ 38,077) $150,000 1% ($134,231) $250,000 1% ($230,385) $ 5,000 Expected value $ 5,192 Cond’l loss severity ($110,193)
ERD example • Simple example of ERD calculation, continued • Probability of net loss = p = 4% • Average conditional loss severity: (38,077 x 2% + 134,231 x 1% +230,385 x 1%) / 4% • “T” = TVaR(96%) = $110,193 • ERD = pT / P = (4%) (110,193) / 10,000 = 44.1% • By comparison, 10% chance of 10% loss = 1.0% ERD
ERD steps • 1. Produce the probability distribution of net present value gain, including all flows (real examples have more flows). • 2. Identify the “risk zone” part of the distribution containing net losses. • 3. Measure probability of loss and average conditional severity when it occurs. • 4. Apply the ERD formula.
Comparisons to other metrics • Other popular metrics have a similar structure: • Based on distribution of a key financial item • Specific threshold point of the distribution • Measurement of frequency and/or severity • VaR (value-at-risk): • Key financial item: net gain / (loss) of capital • Threshold point: Percentile, such as 5th • Measurement is severity of percentile point • “What level of loss is possible at an outside chance?” • 10/10 rule: VaR(90%) > 10% of premium • Fixes frequency independently of particular contract’s details • Doesn’t measure severity beyond percentile
Comparison to other metrics • TVaR (tail value-at-risk), CTE (conditional tail expectation): • Key financial item: net gain in capital, or net economic gain • Threshold point: Percentile, such as 5th • Measurement is average severity beyond percentile point (“tail”) • “What’s the average loss of capital in the worst 5% of cases?” • Fixes frequency independently of particular contract’s details • Doesn’t capture the likelihood of a net loss • ERD connection: T = TVaR(1-p), p = probability of loss • 10/10 rule: A contract passing 10/10 will pass a 1% ERD test, but not the other way around – cat excess example
Risk coverage ratio (RCR) • Replace ERD’s premium denominator with expected gain from NPV distribution (“E[G]” in formulas below) • Formulas: As risk per $1 of return: RCR, % form = pT / E[G] As expected profit per unit of risk assumed: RCR = E[G] / pT • All components come from the economic gain distribution • Risk / return metric on economic value
RCR example • Same example as above • Probability of net loss = p = 4% • Average conditional loss severity = T = $110,193 • E[G] = Expected gain = $5,192 • RCR % = pT / E[G] = (4%) (110,193) / 5,192 = 84.9% • Risk concentration embedded in expected return = 84.9%
Advantages / applications • Advantages of ERD and RCR • Cutoff point is economic breakeven, rather than a statistical percentile • Realized impact of risk on companies is in dollar, rather than percentile, terms • Includes all loss events, rather than only the most extreme events • Captures both frequency and severity in one metric • RCR is not affected by “traded dollars” in premium • RCR measures the risk/return tradeoff in terms of economic gain • Applications of RCR • Risk-based pricing • Risk-based capital allocation (see paper for reference)
Right-tailed deviation (RTD) • Some Working Party members prefer risk measures based on distributional transforms over ERD • Transforms may have added benefits, some added complexity • Right-tailed deviation (RTD) proposed by Shaun Wang Define F*(x) = 1 – [1 – F(x)] 0.5 • F* is F with the tail stretched out – a risk-loaded distribution F*(x) ≤ F(x), which means E* ≥ E RTD = E* – E = risk load
RTD example • Loss distribution (dollars in $000) Ceded lossF(x)F*(x) $ 0 96% 80% $ 50,000 98% 86% $150,000 99% 90% $250,000 100% 100% Expected value $5,000 $34,000 RTD = $34,000 - $5,000 = $29,000
RTD example • RTD risk transfer test: Maximum qualified premium = α(RTD) • α parameter could be between 3 and 5; WP observed 4 may be too low. • In example, using α = 5: Maximum qualified premium = $145m
RTD advantages • F*(x) is a new “loss” distribution – all the usual methods apply • Easy to risk-price layers of coverage • Other advantages – see Wang’s papers • “Maximum qualified premium” concept opens door to qualifying part of premium in some cases, instead of “all or nothing”
Conclusion • The WP Report is a significant contribution to the literature on risk transfer: • Defined a structured process to narrow down contracts that have to be tested • Described two risk metrics that appear superior to the 10-10 test: ERD and RTD • 1% ERD suggested as one possible threshold
Conclusion • Further research recommended: • Level 1: Consensus thresholds • Level 2: Other methods, including quantitative definitions of terms and incorporating parameter uncertainty • (Paper only) 3rd research area: Develop the actuarial perspective on risk transfer, independent of current accounting rules.