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CAS Exam 8 · Retrospective Plan Parameters · Tutorial 621 of 989

Apply Per-Claim Loss Limits Before Conversion

Apply a per-claim loss cap in the correct order, calculate converted losses, and determine its effect on retrospective premium.

Advanced 13 min read

What You'll Learn

  • Define eligible loss amounts and a per-claim maximum on the correct basis
  • Calculate each claim’s capped amount before applying the loss conversion factor
  • Sum capped amounts and convert them to plan losses
  • Apply a stated retrospective premium formula and test its premium bounds
  • Identify why capping converted losses at the unadjusted claim limit is generally incorrect

Why the Order of Operations Matters

A retrospective rating plan can use a per-claim maximum to limit how much of any one claim enters the loss component of the premium calculation. The order is essential: first cap each eligible claim amount at the plan’s stated maximum, then apply the loss conversion factor (LCF) to the capped amount. Applying the LCF first and using the same unadjusted cap afterward generally changes the result.

This tutorial focuses on a per-claim cap defined on eligible loss before conversion. It does not assume that the cap applies to converted losses, nor does it treat a per-claim cap as an aggregate limit. The plan wording controls the basis and order. The examples use hypothetical plans with all amounts evaluated on the same stated basis.

Definition: Let \(X_j\) be the eligible loss amount for claim \(j\), and let \(C\) be the plan’s per-claim maximum, both measured on the same basis. The limited amount for claim \(j\) is \(L_j=\min(X_j,C)\). For a positive loss conversion factor \(\lambda\), the converted amount is \(\lambda L_j\). Thus the per-claim limit is applied to each \(X_j\) before conversion.

“Eligible loss” must be read from the plan terms. It may refer to incurred losses on a specified valuation date or to another defined loss basis. Do not silently add or remove an expense component, change the valuation date, or apply an inflation adjustment unless the plan specifies that treatment. The examples state their eligible amounts directly so the calculation order is clear.

The Calculation in Three Stages

For a set of claims subject to the same per-claim maximum and LCF, the calculation has three stages: limit each claim, add the limited amounts, and convert the resulting sum. If the plan uses different limits or factors for different claims, each claim must instead use its own stated plan parameters.

$$ L_j=\min(X_j,C),\qquad L_{\mathrm{total}}=\sum_{j=1}^{n}L_j,\qquad L_{\mathrm{converted}}=\lambda L_{\mathrm{total}} $$

To show how the converted losses feed into premium, suppose the stated plan formula is a basic premium \(B\) plus converted losses, subject to a minimum premium \(P_{\min}\) and maximum premium \(P_{\max}\). For this formula, the indicated premium is \(B+L_{\mathrm{converted}}\); the actual premium is then bounded as follows. This is a deliberately specified formula for the examples, not a claim that every retrospective plan uses identical terms.

$$ P=\min\!\left(P_{\max}, \max\!\left(P_{\min},B+\lambda\sum_{j=1}^{n}\min(X_j,C)\right)\right) $$

The premium bounds are applied to the plan’s indicated premium. They do not change the claim-by-claim limitation or the calculation of converted losses. If the indicated premium is below the minimum, the actual premium is the minimum; if it exceeds the maximum, the actual premium is the maximum; otherwise, it is unchanged.

Why the Cap Must Precede Conversion

The order follows from what the plan defines as its limited amount. The cap is a maximum on \(X_j\), the eligible loss before conversion. Therefore, first select the smaller of \(X_j\) and \(C\), then multiply that result by \(\lambda\). The LCF changes the capped amount; it does not change which amount the original cap is defined to limit.

1
Compare the claim with the cap.
For each claim, calculate \(L_j=\min(X_j,C)\). A claim below the cap remains unchanged; a claim above it is reduced to the cap.
2
Add the limited claim amounts.
Calculate \(L_{\mathrm{total}}=\sum_j L_j\). This is the loss amount to which the stated LCF applies.
3
Convert and calculate premium.
Multiply \(L_{\mathrm{total}}\) by the LCF, add the converted losses to the plan’s other specified premium components, and then apply any premium bounds.

A short algebraic check clarifies a common source of error. For a positive \(\lambda\), multiplying a correctly capped loss by \(\lambda\) gives \(\lambda\min(X_j,C)\). If one instead caps the converted loss at \(C\), the calculation becomes \(\min(\lambda X_j,C)\). These are not generally equal. For example, when \(X_j>C\) and \(\lambda>1\), the correct result is \(\lambda C\), while the incorrect result is \(C\). A cap defined after conversion would require different plan wording and a different basis for the limit.

$$ \lambda\min(X_j,C)=\min(\lambda X_j,\lambda C) \quad\text{for }\lambda>0, \qquad \text{but generally }\min(\lambda X_j,C)\ne\lambda\min(X_j,C) $$

The first equality follows because multiplying both candidates \(X_j\) and \(C\) by the same positive number preserves their order. The second expression keeps the cap at \(C\) rather than converting the cap to \(\lambda C\), so it imposes a different maximum whenever the LCF changes the loss amount.

Worked Calculations

Worked Example: Applying the Cap Before Conversion

A hypothetical plan has three eligible claims of \( \$18{,}000\), \( \$43{,}000\), and \( \$76{,}000\). Its per-claim maximum is \(C=\$50{,}000\), its LCF is \(\lambda=1.12\), its basic premium is \(B=\$120{,}000\), and its premium bounds are \(P_{\min}=\$200{,}000\) and \(P_{\max}=\$300{,}000\). Use the specified formula \(P=\min(P_{\max},\max(P_{\min},B+L_{\mathrm{converted}}))\). All amounts are hypothetical and in dollars.

Method. Limit each eligible claim first, then sum and convert.

For claim 1, \(L_1=\min(\$18{,}000,\$50{,}000)=\$18{,}000\). For claim 2, \(L_2=\min(\$43{,}000,\$50{,}000)=\$43{,}000\). For claim 3, \(L_3=\min(\$76{,}000,\$50{,}000)=\$50{,}000\).

The limited total is \(\$18{,}000+\$43{,}000+\$50{,}000=\$111{,}000\). The converted losses are \(1.12\times \$111{,}000=\$124{,}320\). The indicated premium is \(\$120{,}000+\$124{,}320=\$244{,}320\).

Since \(\$200{,}000\le \$244{,}320\le \$300{,}000\), neither premium bound applies. The actual premium is \(\$244{,}320\).

Check and common mistake avoided. Exactly one claim exceeds the cap, so the limited total is \(\$111{,}000\), not the original \(\$137{,}000\). The calculation applies the cap to that claim before multiplying the total by 1.12.

Worked Example: Recognizing When the Minimum Premium Binds

A hypothetical policy has one eligible claim of \(\$80{,}000\), a pre-conversion per-claim maximum of \(\$60{,}000\), and an LCF of 1.25. Its basic premium is \(\$90{,}000\), with a minimum premium of \(\$170{,}000\) and a maximum of \(\$220{,}000\). Calculate the converted loss and actual premium.

Method. Apply the cap to the eligible claim, convert, and only then test the indicated premium against the bounds.

The limited claim is \(\min(\$80{,}000,\$60{,}000)=\$60{,}000\). The converted loss is \(1.25\times \$60{,}000=\$75{,}000\). Adding the basic premium gives an indicated premium of \(\$90{,}000+\$75{,}000=\$165{,}000\).

The indicated premium is below the \(\$170{,}000\) minimum. It is also below the \(\$220{,}000\) maximum, so the minimum is the binding bound and the actual premium is \(\$170{,}000\).

Check and common mistake avoided. The converted losses remain \(\$75{,}000\), even though the premium is raised to the minimum. The minimum premium does not replace or revise the claim limit.

Worked Example: Finding Which Premium Bound Applies

A hypothetical plan has eligible claims of \(\$12{,}400\), \(\$35{,}600\), \(\$64{,}800\), and \(\$92{,}000\). Each claim has a pre-conversion maximum of \(\$70{,}000\). The LCF is 1.08, the basic premium is \(\$210{,}000\), and the premium bounds are \(\$250{,}000\) and \(\$400{,}000\). Find the converted losses and actual premium.

Method. Cap the fourth claim, which exceeds \(\$70{,}000\), and retain the first three claims because each is below the cap.

The limited amounts are \(\$12{,}400\), \(\$35{,}600\), \(\$64{,}800\), and \(\$70{,}000\). Their sum is \(\$12{,}400+\$35{,}600+\$64{,}800+\$70{,}000=\$182{,}800\). Converted losses are \(1.08\times \$182{,}800=\$197{,}424\).

The indicated premium is \(\$210{,}000+\$197{,}424=\$407{,}424\). Since this is greater than the \(\$400{,}000\) maximum, the maximum binds. The actual premium is \(\$400{,}000\).

Check and common mistake avoided. The limited total is less than the original claim total of \(\$204{,}800\) by \(\$22{,}000\), exactly the amount by which the fourth claim exceeds its cap. The premium is capped only after conversion and addition to the basic premium.

Common Error: Capping Converted Losses at the Original Limit

A frequent error is to calculate \(\min(\lambda X_j,C)\) when the plan says the cap applies to eligible losses before conversion. That expression applies the original dollar cap to a different quantity: the converted loss. It can materially understate converted losses when \(\lambda>1\), and it can also give a different result when \(\lambda<1\).

For example, with \(X_j=\$80{,}000\), \(C=\$60{,}000\), and \(\lambda=1.25\), the correct limited amount is \(\min(\$80{,}000,\$60{,}000)=\$60{,}000\), and the converted amount is \(1.25\times \$60{,}000=\$75{,}000\). The wrong order gives \(\min(1.25\times \$80{,}000,\$60{,}000)=\min(\$100{,}000,\$60{,}000)=\$60{,}000\). The error understates converted losses by \(\$15{,}000\).

A related mistake is to apply one cap to the sum of all claims. That is not the same operation as limiting each claim separately: several claims can each contribute up to \(C\). Always identify whether the stated plan term is per claim or applies to a different total. For this calculation, the required operation is the individual claim limit defined by the plan.

Key takeaway: When the plan defines a per-claim maximum on eligible loss before conversion, calculate \(\min(X_j,C)\) for every claim, add those limited amounts, apply the LCF, and then calculate premium and test its bounds. Do not reuse the unconverted cap on converted losses.

Check Your Understanding

For each hypothetical plan, follow the stated order and use the stated premium formula. Amounts are in dollars. Answers are shown so you can check the intermediate logic as well as the final result.

  1. A claim is \(\$26{,}000\), the pre-conversion maximum is \(\$40{,}000\), the LCF is 1.15, and the basic premium is \(\$75{,}000\). The minimum and maximum premiums are \(\$80{,}000\) and \(\$130{,}000\). What are the converted losses and actual premium? (Answer: limited loss \(\$26{,}000\), converted losses \(\$29{,}900\), actual premium \(\$104{,}900\).)
  2. Two claims are \(\$9{,}000\) and \(\$48{,}000\). The per-claim maximum is \(\$35{,}000\), the LCF is 1.20, and the basic premium is \(\$100{,}000\). The bounds are \(\$120{,}000\) and \(\$180{,}000\). Calculate the limited total, converted losses, and actual premium. (Answer: limited total \(\$44{,}000\), converted losses \(\$52{,}800\), actual premium \(\$152{,}800\).)
  3. A single eligible claim is \(\$90{,}000\), the per-claim maximum is \(\$55{,}000\), the LCF is 1.10, and the basic premium is \(\$140{,}000\). The premium bounds are \(\$170{,}000\) and \(\$230{,}000\). What premium is charged? (Answer: limited loss \(\$55{,}000\), converted losses \(\$60{,}500\), indicated and actual premium \(\$200{,}500\).)
  4. Claims are \(\$20{,}000\), \(\$50{,}000\), and \(\$80{,}000\), each subject to a \(\$45{,}000\) pre-conversion maximum. The LCF is 1.30, the basic premium is \(\$80{,}000\), and the bounds are \(\$100{,}000\) and \(\$220{,}000\). Find the actual premium. (Answer: limited total \(\$110{,}000\), converted losses \(\$143{,}000\), indicated premium \(\$223{,}000\), actual premium \(\$220{,}000\).)
  5. For one claim, \(X_j=\$72{,}000\), \(C=\$50{,}000\), and \(\lambda=1.20\). The basic premium is \(\$100{,}000\), with bounds of \(\$100{,}000\) and \(\$165{,}000\). Compare the correct actual premium with the result of incorrectly capping converted loss at the original \(C\). (Answer: correct converted loss \(\$60{,}000\), indicated and actual premium \(\$160{,}000\); wrong converted loss \(\$50{,}000\), wrong premium \(\$150{,}000\).)
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