Why Claim Timing Matters in an Asset-Share Year
A death benefit is a cash outflow from the insurer, but its effect on an annual asset-share ledger depends on when it is paid. A claim settled at midyear does not earn a full year of investment return after payment; a claim expense paid at year-end earns no return during that year. Treating both amounts as if paid at the same date can materially misstate the year-end value of claim outgo.
This tutorial considers the claim side of an annual asset-share calculation. It distinguishes actual claims from expected claims, and death payments from funds that remain for policies still in force. All products and figures below are hypothetical. The method is aligned with the SOA Exam ALTAM (Advanced Long-Term Actuarial Mathematics) syllabus.
Let \(i\) be the effective annual investment return, and let \(\tau\) be the fraction of the policy year elapsed when a payment is made, where \(0\leq \tau\leq 1\). A payment \(C\) made at time \(\tau\) has year-end accumulated value \(C(1+i)^{1-\tau}\). This is an accumulation convention: it values the cash outflow at year-end, not the date on which the insurer actually pays it.
Expected and Actual Claim Outgo
Suppose \(N\) policies are in force at the start of a year. Under a homogeneous mortality assumption, let \({}_1q_x\) be the probability that a policy in force at age \(x\) experiences death during the year. The expected number of deaths is \(N\,{}_1q_x\). This is an expectation, not a forecast that the actual number of claims must equal that value.
If each death benefit \(B\) and claim expense \(E\) are both paid at the same time \(\tau\), the expected year-end claim outgo for the starting group is \(N\,{}_1q_x(B+E)(1+i)^{1-\tau}\). If the benefit and expense are paid at different times, accumulate them separately. For an observed group with \(D\) actual claims, use \(D\), rather than \(N\,{}_1q_x\), to calculate the actual claim outgo.
The expected group outgo is \(N\) times this amount. This formula assumes the stated benefit, expense and payment times apply to every death in the group, and that the same annual effective return is used over the relevant part of the year. It does not apply unchanged if claim amounts or timing vary by claim; in that case, calculate and sum the appropriate expected payment values by claim type or time.
Worked Example: Accumulating a Midyear Death Claim
A hypothetical policy has a death benefit of $30,000. A further $750 of claim expense is paid at the same time as the benefit, exactly halfway through the policy year. The annual effective investment return is 21%. Find the year-end accumulated value of this claim outgo. The policy's mortality assumption is not needed because this is the outgo conditional on a claim having occurred.
Method. Combine the payments made on the same date, then accumulate them for the remaining half-year. The half-year accumulation factor is \((1.21)^{0.5}=1.1\), since \(1.1^2=1.21\).
The amount paid at midyear is
The time remaining until year-end is \(1-0.5=0.5\) years, so the accumulated outgo is
Check. The year-end value exceeds the $30,750 actually paid because the insurer forgoes investment return on that money for half a year. The calculation avoids treating a midyear payment as if it were paid at the start of the year.
Why the Accumulation Formula Holds
The time from a payment at \(\tau\) to the end of the year is \(1-\tau\) years. Under a constant effective annual return \(i\), an amount invested for \(t\) years accumulates by the factor \((1+i)^t\). To express an outflow at its year-end equivalent, accumulate the payment over exactly the time it is absent from the fund. Therefore, a payment \(C\) at time \(\tau\) has year-end value \(C(1+i)^{1-\tau}\). The exponent is the remaining fraction of the year, not the elapsed fraction.
If there are several payments \(C_j\) at times \(\tau_j\), accumulation is applied payment by payment, because each amount is absent from the fund for a different length of time:
This result assumes the same effective annual return applies over the year. If the return changes during the year, each payment must instead be accumulated using the return factors for the intervals remaining after its payment date. If the asset-share convention records cash flows at their actual dates without accumulating each to year-end, use those actual-date cash flows consistently rather than adding an extra accumulation.
Worked Example: Expected Outgo for a Starting Cohort
A hypothetical block has 240 identical policies in force at the start of the year. Each policy has a one-year death probability of \(0.025\). A $25,000 death benefit and a $500 claim expense are both paid at midyear on death. The annual effective return is 21%. Calculate (a) the expected number of claims, (b) expected year-end claim outgo for the block, and (c) expected year-end outgo per policy in force at the start of the year.
Method. First calculate expected claims from the starting count and mortality probability. Then calculate the year-end value for one claim and multiply by the expected count.
(a) The expected number of claims is
(b) One claim, including its expense, pays \(25{,}000+500=\$25{,}500\) at midyear. The remaining-half-year accumulation factor is \((1.21)^{0.5}=1.1\), so the year-end value per claim is
Thus, expected year-end block outgo is
(c) Divide by the 240 policies at the start of the year—not by an assumed year-end count—to obtain
per starting policy. Equivalently, \(0.025(28{,}050)=\$701.25\). The expected count of six is appropriate for an expected-value calculation; it need not be an integer in other problems. This is an expected claim cost per starting policy, not an amount paid by every policy.
Check. Multiplying the per-starting-policy amount by 240 returns $168,300. The denominator refers to the population exposed to the year's mortality risk.
Claim Outgo in the Asset-Share Ledger
An annual asset-share recurrence records premiums and expenses, investment accumulation, and benefits according to the chosen cash-flow timing convention. For the claim component, the key operation is to subtract death benefits and claim expenses when they are paid, or subtract their consistently accumulated equivalents when expressing the ledger at year-end. A claim already paid during the year must not be subtracted again as a second year-end payment.
The cohort perspective and the individual-policy perspective answer different questions. At cohort level, death claims are insurer outgo on policies that terminate because of death. For a policy that continues in force, no death benefit was paid on that policy during the year; its own continuing-policy ledger does not acquire a death payment merely because another policy in the cohort claimed. An aggregate asset-share calculation may include all cohort claims as outgo from the aggregate fund, but that does not make the death benefit an amount retained by continuing policies. The allocation of aggregate experience among survivors is a distinct calculation.
A useful way to keep the accounting straight is to label each cash flow by its event and payment time before combining it with the rest of the ledger:
Record the policies in force at the start of the year and the mortality assumption used for expected claims.
Use observed claims for an actual experience ledger and \(N\,{}_1q_x\) for an expected-value calculation.
Record the benefit and each claim expense at its own payment time; do not presume they coincide.
Accumulate each payment to year-end if the ledger is stated at year-end, then subtract the resulting outgo once.
Identify whether the calculation concerns a death claim, a continuing policy, or aggregate cohort cash flow.
Worked Example: Separating Claim Payments From Continuing Funds
A hypothetical policy-year cash-flow ledger begins with $10,000. A $1,000 renewal premium is received at the start of the year and a $100 renewal expense is paid then. The effective annual investment return is 21%. If no death claim occurs, all three start-of-year amounts are invested through the year. For a death claim, a $32,000 benefit is paid at midyear and a $300 claim expense at year-end. Calculate the year-end balance before claims, the year-end value of claim outgo, and the resulting balance after claim outgo in this ledger.
Method. Accumulate the opening amount and start-of-year cash flows for a full year. Accumulate the midyear benefit for half a year, but do not accumulate the year-end claim expense.
The amount invested at the start of the year, before claim outgo, is
At the 21% effective annual return, its year-end value before claims is
The $32,000 midyear death benefit has year-end value
The $300 claim expense is paid at year-end, so its year-end value is $300. Total year-end claim outgo is therefore
Subtracting this from the pre-claim year-end balance gives
Interpretation and check. The negative result is the net cash-flow balance in this simplified ledger after the hypothetical claim outgo; it indicates that the listed inflows alone do not cover the claim. It is not an amount retained for a continuing policy, nor a claim benefit paid to one. The benefit is paid on the policy that dies; a policy that continues has no such death payment in its own cash-flow record.
Common Exam Trap: Using a Full-Year Accumulation Factor
A frequent timing error is to multiply every claim paid during the year by \(1+i\), regardless of its payment date. For the midyear claim in the first worked example, the incorrect calculation would be
That treats the $30,750 as if it were paid at the beginning of the year and were absent from the fund for a full year. The correct year-end value is \(30{,}750(1.21)^{0.5}=\$33{,}825.00\). The overstatement is \(\$37{,}207.50-\$33{,}825.00=\$3{,}382.50\). Conversely, leaving the amount at its nominal payment value understates its year-end equivalent when the payment occurs before year-end and \(i>0\).
Before using any claim amount in an annual recurrence, check three things: whether it is actual or expected, whether the expense is included, and what fraction of the year remains after payment. Also check the denominator: expected outgo per starting policy is divided by the number exposed at the start, not automatically by the number still in force at year-end.
Check Your Understanding
For each problem, show the payment timing before calculating. Answers are stated for checking.
- A hypothetical block has 160 policies in force at the start of the year and a one-year death probability of \(0.0125\). Each death claim pays a benefit of $18,000 and claim expense of $400, both at midyear. The annual effective return is 21%. Find the expected year-end claim outgo for the block. (Answer: $40,480)
- A block has 100 starting policies and a one-year death probability of \(0.04\). On each death, a $10,000 benefit is paid at midyear and $200 of claim expense is paid at year-end. The half-year accumulation factor is 1.1. Find expected year-end claim outgo for the block. (Answer: $44,800)
- A hypothetical cohort has 500 policies in force at the start of the year, each with a death probability of \(0.02\). A $40,000 benefit and $600 claim expense are paid at midyear on death. The annual effective return is 21%. Find the expected year-end outgo per starting policy and for the whole cohort. (Answer: $893.20 per starting policy; $446,600 for the cohort)
- A policy has a $20,000 death benefit paid at midyear and a $500 claim expense paid at year-end. The annual effective return is 21%. Find the year-end value of the claim outgo. (Answer: $22,500)
- In an aggregate asset-share ledger, one policy in a cohort dies during the year and another continues. State whether the death benefit is a death payment on the continuing policy's own ledger, and explain how the claim should be described at cohort level. (Answer: No; it is outgo on the policy that dies and is included as claim outgo in the aggregate cohort cash flow.)