Actuarial Notes

Claim Reserve

Study guides: Exam CP-321, Exam GH-201C, Exam GH-201U

A claim reserve is the liability a health or group insurer holds at the valuation date for benefits on claims incurred on or before that date but not yet paid — reported claims still in course of settlement, claims incurred but not reported (IBNR), and, on disability and long-term care claims, the present value of benefits not yet due. It is the health counterpart of P&C unpaid claims, and it is distinct from the non-claim reserves (policy, unearned premium and premium deficiency reserves) held for coverage not yet provided.

\hat{C}_m = \frac{P_m}{CF_{k(m)}}

\hat{R} = \sum_m \left(\hat{C}_m - P_m\right)

\text{DLR} = \sum_{t \geq 0} v^{t}\, {}_{t}p^{\,d}\, B_t

  • Completion factor method (short-duration medical, dental, drug): P_m is claims incurred in month m and paid to date, k(m) the months of lag since m, and CF_k the share of ultimate incurred claims paid by lag k, read off a lag triangle as the reciprocal of the product of the remaining age-to-age factors. It is the chain ladder stated as a percentage complete.
  • For the most recent incurral months CF_k is small, so 1/CF_k magnifies any noise in P_m. Practice replaces those months with a projection (expected PMPM \times members, trended), or blends the two.
  • Disabled life reserve (LTD, LTC, waiver of premium): for an open claim, B_t is the benefit due at time t and {}_tp^{\,d} the probability the claimant is still disabled (claim termination by recovery or death). CP-321 names the pieces for long-duration contracts: the present value of amounts not yet due (PVANYD), claims in course of settlement (ICOS) and IBNR.
  • ASOP 5 defines the unpaid claims liability as the unpaid portion of incurred claims, including unreported and reported-but-unpaid claims. Environmental changes — trend, seasonality, claim processing speed — distort completion factors, which is why the syllabus asks you to evaluate them.

Completion Factor Reserve with a Projected Recent Month A medical plan values claims at May 31. Cumulative paid claims (\$000) by incurral month and lag in months:

Incurred Lag 0 Lag 1 Lag 2 Lag 3 Lag 4
Jan 420 860 960 990 1,000
Feb 400 830 925 955
Mar 450 920 1,030
Apr 430 880
May 470

Claims are complete by lag 4. Using volume-weighted age-to-age factors, compute the claim reserve. Then replace May with a projection of \$101.50 PMPM on 10{,}200 members.

Answer Age-to-age factors, then completion factors (product of the remaining factors, inverted):

\begin{align*}
f_{0 \to 1} &= \tfrac{3{,}490}{1{,}700} \\
&= 2.0529 \\
f_{1 \to 2} &= \tfrac{2{,}915}{2{,}610} \\
&= 1.1169 \\
f_{2 \to 3} &= \tfrac{1{,}945}{1{,}885} \\
&= 1.0318 \\
f_{3 \to 4} &= \tfrac{1{,}000}{990} \\
&= 1.0101
\end{align*}

CF_4 = 1, CF_3 = 0.9900, CF_2 = 0.9595, CF_1 = 0.8591, CF_0 = 0.4185. Reserve by month, P_m(1/CF - 1):

\begin{align*}
\text{Feb} &= 955/0.9900 - 955 \\
&= 9.6 \\
\text{Mar} &= 1{,}030/0.9595 - 1{,}030 \\
&= 43.5 \\
\text{Apr} &= 880/0.8591 - 880 \\
&= 144.3 \\
\text{May} &= 470/0.4185 - 470 \\
&= 653.1 \\
\hat{R} &= 850.5
\end{align*}

May's completion estimate implies 1{,}123.1/10.2 = \$110.10 PMPM, well above the projection. Replacing May:

\begin{align*}
\hat{C}_{\text{May}} &= 10{,}200 \times 101.50 / 1{,}000 \\
&= 1{,}035.3 \\
\hat{R} &= 197.5 + (1{,}035.3 - 470) \\
&= 762.8
\end{align*}

The reserve is \$762.8K rather than \$850.5K. With only 42% of May paid, an unusually fast first month of payments was being multiplied by 2.39; the projection gives that month the weight its data deserves.

Disabled Life Reserve on an Open LTD Claim A disabled claimant receives \$36{,}000 a year, paid at the start of each year, for at most three more payments. The probabilities the claim is still open at times 1 and 2 are 0.80 and 0.68. At 4\% interest, compute the reserve for amounts not yet due.

Answer

\begin{align*}
\text{DLR} &= 36{,}000\left(1 + 0.80v + 0.68v^{2}\right) \\
&= 36{,}000\,(1 + 0.7692 + 0.6287) \\
&= 36{,}000 \times 2.3979 \\
&= 86{,}325
\end{align*}

The reserve is \$86{,}325. Ignoring claim terminations would give \$103{,}899 — termination rates, not interest, drive this reserve.

How it appears on the exam

  • GH-201U and GH-201C (objective 3, "calculate appropriate claim reserves given data"): a lag triangle of paid claims plus membership, asking for completion factors, the reserve, and a judgement on the most recent months — usually blended with a PMPM projection.
  • GH-201 objective 4 pairs the calculation with an environmental change (a processing backlog, a seasonal spike, a trend shift) and asks how the factors and reserve move, in writing.
  • "Describe the types of claim reserves" (GH-201 objective 1) is a written list: reported but unpaid, IBNR, PVANYD on long-duration claims, and claim adjustment expense, set apart from non-claim reserves.
  • CP-321 objective 4 moves to long-duration contracts: a disabled life or LTC claim reserve from termination rates and interest, alongside policy and premium deficiency reserves.

Exam traps

  • Inverting the wrong way: a completion factor is below 1 and you divide paid by it. Multiplying gives a reserve that is negative.
  • Trusting lag-0 completion: dividing a recent month by a factor near 0.4 turns a 10% blip in paid into a 10% error in that month's ultimate. Projection or blending is expected for recent months.
  • Not adjusting for a processing speed-up: faster payment raises recent paid amounts, and historical completion factors then overstate the reserve.
  • Calling a disabled life reserve IBNR: the claim is reported; its future benefits are amounts not yet due, valued with termination rates.