Not a goal in itself
Used to make further calculations, like adequacy of business unit profits, incentive compensation
Can also be used for strategic planning:
– Would growing this business unit by 10% generate enough profits to make up for the cost of the capital it would need?
Best methods to some extent depend on purpose of allocation
1.
Divide return by allocated capital
Allocate capital by some risk measure and divide
2.
Compare return to price of bearing risk
Use a theory of market risk pricing to set targets
3.
Charge actual marginal capital costs against profits
Compare the profits expected from a strategic plan to the cost of the extra total capital the firm needs
Direct marginal cost – not an allocation
4.
Compare value of float generated by the business to a leveraged investment fund with the same risk
Do for whole firm, then look at marginal impact of business unit or growth plan
Take one from each column and mix carefully
Risk Measures
– VaR
– EPD
– Tail VaR
– X TVaR
– Standard Deviation
– Variance
– Semi-Variance
– Cost of Default Option
– Mean of Transformed
Loss
Allocation Methods
– Proportional Spread
– Marginal Analysis
• By whole business unit
• Increment of business unit
– Game Theory
– Equalize Relative Risk
– Apply Co-Measure
Suppose a risk measure for risk X with mean m can be defined as:
– R(X) = E[(X – am)g(x)|condition] for some value a and function g
– X is the sum of n portfolios X i each with mean m i
Then co-measure for X
– CoR(X i
) = E[(X i i is:
– am i
)g(x)|condition]
– Note that CoR(X
1
)+CoR(X
2
) = CoR(X the sum of the CoR’s of the n X
1
+X i
’s is R(X)
2
) and so
A risk measure could have equivalent definitions with different a’s and g’s so alternative co-measures
TVAR q
= E[X|X>q]
Co-TVaR q
(X i
) = E[X i
|X>q]
Charges each sub-portfolio for its part of total losses in those cases where total losses exceed threshold value
In simulation, cases where condition is met are selected, and losses of sub-portfolio measured in those cases
XTVAR q
= E[X – m|X>q]
Co- XTVAR q
= E[X i
– m i
|X>q]
Allocates average loss excess of mean when total losses are above the target value
Allocates nothing to a constant X i
Overall capital: target default put cost as % of expected losses
– Limited capital of an insurer gives it an implicit option to put losses that exceed capital to the policyholders
Allocation method is incremental marginal
– Last dollar of expected loss in a business unit is charged with the capital needed to keep the company put cost ratio constant
– The whole business unit (or policy) gets charged at that ratio to expected losses – a pure marginal method
But all capital is allocated, as the sum of the marginal capital charges equals the whole capital of the firm
– From the additivity of option prices
A constant risk generally gets a negative capital charge
– It does not add risk but both adds stability and accepts risk of non-payment
Myers-Read and Co-XTVaR both additive and reasonable
But pricing to equalize returns on capital so allocated may not tie in to risk pricing standards
Myers-Read do not advocate pricing purely in proportion to allocated capital – a risk charge is also added e.g. for covariance with market
Makes most sense for allocation of frictional costs
– Costs from holding capital even if no risk taken
– Cost is proportional to capital
CAPM might be starting point
Company-specific risk needs to be reflected
– Froot-Stein, Mayers-Smith
The estimation of beta itself is not an easy matter
– Full information betas
Other factors besides beta are needed to account for actual risk pricing
– Fama and French Multifactor Explanations of Asset Pricing
Anomalies
Heavy tail beyond variance and covariance
– Wang A Universal Framework For Pricing Financial And
Insurance Risks
– Kozik and Larson The N-Moment Insurance CAPM PCAS 2001
Impact of jump risk
Instead of return rate, subtract cost of capital from unit profitability
Use true marginal capital costs of business being evaluated, instead of an allocation of entire firm capital
– If evaluating growing the business 10%, charge the cost of the capital needed for that much growth
– If evaluating stopping writing in a line, use the capital that the company would save by eliminating that line
This maintains financial principle of comparing profits to marginal costs
Could use change in overall risk measure of firm that results from the marginal business – but requires selection of the overall risk measure
Or could set capital cost of a business segment as the value of the financial guarantee the firm provides to the clients of the business segment
Cost of capital for subsidiary is a difference between two put options:
– 1. The cost of the guarantee provided by the corporation to cover any losses of the subsidiary
– 2. The cost to the clients of the subsidiary in the event of the bankruptcy of the corporation
Economic value added of the subsidiary is value of profit less cost of capital
– Value of profit is contingent value of profit stream if positive
A pricing method for heavy-tailed contingent claims would be needed
Insurer can be viewed as a tax-disadvantaged leveraged mutual fund
– Combined ratio less 100% is cost of funds
Measure mean and risk for insurer’s post-tax return
Then find parameters for mutual fund that give same after-tax distribution of return
– Find amount to be borrowed, investment mix, and borrowing rate
Evaluate financial worth of writing the insurance by the risk-equivalent borrowing rate
– A high rate easy to obtain says writing insurance is not adding value
– A low risk-equivalent rate indicates value is added
Business units can be evaluated based on their marginal impact on the equivalent borrowing rate
Allocating by risk measure straightforward but arbitrary and might be allocating fixed capital costs; works for allocating frictional costs
Using risk pricing appropriate for profitability comparison but requires a good theory of pricing
Actual marginal surplus most useful for determining economic contributions of business units. This is not the same as allocation in proportion to marginal risk.
Leveraged mutual fund comparison a basically qualitative method for evaluating return on total capital and the marginal contribution of each business unit to that