Tutorials › CAS Exam 9 - Risk Management for Actuaries › Deriving a RAROC Hurdle Rate

CAS Exam 9 · Capital and Performance Decisions · Tutorial 378 of 995

Deriving a RAROC Hurdle Rate

Learn to convert a required after-tax return into a consistent RAROC hurdle and adjust it for taxes, financing assumptions, and the chosen capital measure.

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What You'll Learn

  • Derive the required pretax profit from a target after-tax return on capital.
  • Distinguish pretax RAROC hurdles from after-tax hurdles.
  • Match tax treatment in the earnings numerator to the hurdle calculation.
  • Account consistently for deductible financing costs.
  • Explain how changing the capital basis changes the required profit.

Why a RAROC Hurdle Must Match Its Inputs

A RAROC hurdle is the minimum risk-adjusted return needed to meet a specified return requirement on capital. Deriving it is more than choosing a percentage: the earnings measure, tax treatment, financing assumptions, capital basis, and measurement period must be consistent. A threshold built from after-tax equity returns cannot be compared directly with pretax earnings divided by a different capital measure.

The calculations below use hypothetical business results. Unless stated otherwise, amounts are annual, profits are taxable in the year measured, and the tax rate is constant. These simplifying assumptions make the conversion transparent; actual tax positions can require a more detailed model.

Definition: For a specified period, RAROC is risk-adjusted earnings divided by the capital assigned to support the risk over that period. A RAROC hurdle is the minimum RAROC consistent with a stated required return on that same capital basis. Risk-adjusted earnings must be defined explicitly—for example, whether they are before or after financing expense and before or after tax.

Deriving the Tax-Adjusted Hurdle

Let \(K\) be the capital basis, \(k\) the required return on capital after tax, \(\tau\) the effective tax rate on the relevant profit, and \(P\) the annual taxable profit measured before tax. Assume \(K\) is positive, the tax rate applies fully to \(P\), and taxes are paid in the same measurement period. After-tax earnings are then \((1-\tau)P\). To meet the required return, those earnings must be at least \(kK\).

$$ (1-\tau)P \geq kK $$

Dividing both sides by \(1-\tau\), which is positive when \(0 \leq \tau < 1\), gives the minimum pretax profit:

$$ P_{\text{hurdle}}=\frac{kK}{1-\tau} $$

This also gives the pretax RAROC hurdle, when pretax profit is the numerator:

$$ \text{Pretax RAROC}_{\text{hurdle}}=\frac{P_{\text{hurdle}}}{K}=\frac{k}{1-\tau} $$

The derivation explains the gross-up: the business must earn more than the required after-tax amount because only the fraction \(1-\tau\) of taxable profit remains after tax. If the numerator is already after-tax earnings, the corresponding hurdle is simply \(k\). Grossing up an already after-tax numerator would count the tax adjustment twice.

Key result: If the required return \(k\) is after tax and the RAROC numerator is taxable pretax profit \(P\), compare \(P/K\) with \(k/(1-\tau)\). If the numerator is after-tax earnings, compare it with \(k\). The two comparisons are equivalent only when the earnings and tax assumptions match.

Worked Applications

Worked Example: Converting an After-Tax Return Requirement

A hypothetical insurer assigns \(K=\$12.00\) million of capital to a risk portfolio. It requires a 9% annual after-tax return on that capital. Assume taxable pretax risk-adjusted profit is taxed at 25%, with no financing expense. Find the minimum pretax profit and the equivalent pretax RAROC hurdle. Then check whether a pretax profit of \(\$1.50\) million meets the requirement.

Method. The required after-tax earnings are the required return times capital:

$$ kK=0.09(\$12.00\text{ million})=\$1.08\text{ million} $$

At a 25% tax rate, 75% of taxable pretax profit remains after tax. Therefore, the minimum pretax profit is:

$$ P_{\text{hurdle}}=\frac{\$1.08\text{ million}}{1-0.25} =\frac{\$1.08\text{ million}}{0.75} =\$1.44\text{ million} $$

The equivalent pretax RAROC hurdle is:

$$ \frac{\$1.44\text{ million}}{\$12.00\text{ million}} =0.12=12\% $$

For the proposed profit of \(\$1.50\) million, tax is \(0.25(\$1.50\text{ million})=\$0.375\) million, so after-tax earnings are \(\$1.50-\$0.375=\$1.125\) million. The resulting after-tax RAROC is \(\$1.125/\$12.00=9.375\%\). It exceeds the 9% requirement by 0.375 percentage points; the after-tax earnings surplus is \(\$1.125-\$1.08=\$0.045\) million. The equivalent pretax comparison also passes because \(\$1.50\) million exceeds \(\$1.44\) million. Common mistake avoided: comparing a pretax profit ratio with the 9% after-tax requirement without adjusting for tax would use mismatched measures.

Worked Example: The Same Earnings on Two Capital Bases

A hypothetical business reports annual after-tax risk-adjusted earnings of \(\$1.96\) million. Assume the corresponding taxable pretax profit is subject to a 30% tax rate. Management requires a 10% after-tax return. Evaluate the result on two stated capital bases: \(\$16.00\) million and \(\$22.00\) million. For each basis, calculate after-tax RAROC and the minimum pretax profit required.

Step 1: Recover pretax profit. Under the stated tax assumption, after-tax earnings equal 70% of pretax profit. Thus:

$$ P=\frac{\$1.96\text{ million}}{1-0.30} =\frac{\$1.96\text{ million}}{0.70} =\$2.80\text{ million} $$

The implied tax is \(0.30(\$2.80\text{ million})=\$0.84\) million, and \(\$2.80-\$0.84=\$1.96\) million, which checks the conversion.

Step 2: Evaluate the \(\$16.00\) million basis. The after-tax RAROC is \(\$1.96/\$16.00=12.25\%\). The required after-tax earnings are \(0.10(\$16.00)=\$1.60\) million. Converting this requirement to pretax profit gives:

$$ P_{\text{hurdle},16}=\frac{0.10(\$16.00\text{ million})}{0.70} =\$2.285714\ldots\text{ million} \approx \$2.286\text{ million} $$

The actual \(\$2.80\) million pretax profit exceeds this threshold, so the result clears the hurdle on this basis.

Step 3: Evaluate the \(\$22.00\) million basis. The after-tax RAROC is \(\$1.96/\$22.00=8.9091\%\) to four decimal places. Required after-tax earnings are \(0.10(\$22.00)=\$2.20\) million. The pretax hurdle is:

$$ P_{\text{hurdle},22}=\frac{0.10(\$22.00\text{ million})}{0.70} =\$3.142857\ldots\text{ million} \approx \$3.143\text{ million} $$

The actual \(\$2.80\) million pretax profit is below this threshold, so the result misses the hurdle on this basis. The comparison is consistent in after-tax terms as well: \(\$1.96\) million is less than the required \(\$2.20\) million.

Check and common mistake avoided. The pretax thresholds are \(\$1.60/0.70=\$2.286\) million and \(\$2.20/0.70=\$3.143\) million, rounded to the nearest thousand. The figures \(\$1.60\) million and \(\$2.20\) million are the required after-tax earnings, not the pretax thresholds. Using them as pretax hurdles would omit the tax gross-up.

Worked Example: Including a Deductible Financing Expense

A hypothetical lender has \(\$20.00\) million of equity capital and a 12% required after-tax return on that equity. Its annual risk-adjusted operating earnings before financing expense are \(\$4.00\) million. It pays \(\$0.30\) million of interest on borrowed funds; assume this interest is deductible against taxable profit. The tax rate is 25%. Calculate the pretax operating-earnings threshold before financing, and determine whether the stated earnings meet the return requirement.

Method. First specify the numerator: operating earnings before financing. To calculate actual after-tax equity earnings, deduct interest before applying tax. Taxable profit after financing is:

$$ \$4.00\text{ million}-\$0.30\text{ million} =\$3.70\text{ million} $$

Taxes are \(0.25(\$3.70\text{ million})=\$0.925\) million. After-tax earnings available to support the equity return are therefore \(\$3.70-\$0.925=\$2.775\) million. Actual after-tax RAROC on equity is:

$$ \frac{\$2.775\text{ million}}{\$20.00\text{ million}} =13.875\% $$

This exceeds the 12% requirement. To derive the threshold, the required after-tax earnings are \(0.12(\$20.00\text{ million})=\$2.40\) million. The required taxable profit after financing is:

$$ \frac{\$2.40\text{ million}}{1-0.25} =\$3.20\text{ million} $$

Since financing expense is \(\$0.30\) million and is deductible, the required operating earnings before financing are \(\$3.20+\$0.30=\$3.50\) million. The actual \(\$4.00\) million exceeds that threshold by \(\$0.50\) million. As a check, the threshold produces taxable profit of \(\$3.50-\$0.30=\$3.20\) million, after-tax earnings of \(0.75(\$3.20)=\$2.40\) million, and a 12% return on \(\$20.00\) million. Common mistake avoided: treating the pre-financing earnings as taxable profit would ignore the deductible interest and overstate taxes; adding financing expense to the required profit also fails if the numerator has already been defined after financing.

Choose the Capital and Financing Basis Explicitly

The hurdle changes when the capital denominator changes. For a fixed required return \(k\), a larger capital basis requires more earnings: the after-tax target is \(kK\), and the pretax target under the simple tax model is \(kK/(1-\tau)\). The capital basis might be an assigned economic-capital amount, another internally specified capital measure, or equity capital. These bases are not interchangeable; the chosen one must match the return requirement and the purpose of the calculation.

Financing assumptions matter for the same reason. If the numerator is after interest expense and the denominator is equity capital, the comparison should use a return requirement appropriate to that equity basis. If the numerator is before interest, the financing cost must be handled consistently—either deducted in deriving earnings available to capital providers or reflected in the required return under the stated financing model. Do not subtract financing expense from earnings and also include the same expense a second time in the hurdle.

The simple tax gross-up applies only when the stated tax rate applies to the relevant profit and after-tax earnings equal \((1-\tau)P\). It may not apply as written when losses, tax credits, deferred taxes, tax-exempt income, limits on interest deductibility, or other tax effects change the relationship between pretax and after-tax earnings. In those cases, derive the hurdle using the applicable tax model rather than applying a mechanical gross-up.

1
Define the return requirement.
Specify whether the required return is pretax or after tax, its annual or other time period, and the capital basis to which it applies.
2
Define the earnings numerator.
State whether risk-adjusted earnings are before or after financing expense and before or after tax.
3
Convert only what needs conversion.
Under the simple tax model, gross up an after-tax target by dividing by \(1-\tau\) to obtain the required pretax profit. Do not gross up after-tax earnings a second time.
4
Check on a common basis.
Compare actual and required earnings using the same capital, financing, tax, and time-period definitions. Confirm that the implied return meets the stated requirement.

Common Hurdle-Rate Errors

  • Mixing pretax and after-tax measures. A pretax profit ratio cannot be compared directly with an after-tax return requirement unless the tax adjustment has been made.
  • Confusing required earnings with grossed-up earnings. The amount \(kK\) is the required after-tax earnings when \(k\) is an after-tax return. Under the simple tax model, the corresponding pretax threshold is \(kK/(1-\tau)\).
  • Changing the capital basis without recalculating. A hurdle profit computed for one \(K\) does not apply unchanged to a different capital amount.
  • Applying tax to the wrong profit. If deductible financing expense reduces taxable profit, it must be treated consistently in both the actual earnings calculation and the hurdle derivation.
  • Using mismatched periods. Annual earnings should be compared with annual capital returns and a capital basis appropriate to that same period.
Key takeaway: Start with the required return on a specified capital basis. Convert that requirement to a profit threshold using the stated tax and financing assumptions, then compare it with earnings defined on exactly the same basis. The resulting method is aligned with the CAS Exam 9 (Risk Management for Actuaries) syllabus.

Check Your Understanding

For each hypothetical situation, keep the earnings definition, tax treatment, capital basis, and return requirement consistent.

  1. A portfolio has \(\$8.00\) million of capital, an 11% required after-tax return, and a 20% tax rate. Assume there are no financing expenses. What pretax profit is required to meet the hurdle? (Answer: \(\$1.100\) million pretax.)
  2. A unit has \(\$25.00\) million of capital and reports \(\$2.40\) million of after-tax earnings. The required after-tax return is 10%, and the tax rate is 25%. Find its after-tax RAROC and equivalent pretax profit; does it meet the hurdle? (Answer: after-tax RAROC is 9.6000%; pretax profit is \(\$3.200\) million, and it misses the hurdle by \(\$0.100\) million after tax.)
  3. A risk pool has \(\$14.00\) million of capital, a 9% required after-tax return, and a 30% tax rate. With no financing expense, what is the required pretax profit? (Answer: \(\$1.800\) million pretax.)
  4. A portfolio has \(\$18.00\) million of capital and \(\$2.40\) million of taxable pretax profit. The tax rate is 20% and the required after-tax return is 10%. Calculate after-tax RAROC and state whether the hurdle is met. (Answer: after-tax earnings are \(\$1.920\) million, after-tax RAROC is 10.6667%, and the hurdle is met.)
  5. A business has \(\$30.00\) million of equity capital and requires an 8% after-tax return. Its tax rate is 25%; annual interest expense is \(\$0.60\) million and is deductible. What minimum pretax operating earnings before interest are needed? (Answer: \(\$3.800\) million before interest.)
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