Exercise
The exposure is split into three geographic regions: region A, region B and region C. The following accident year 1 data is available:
Region | Current relativity | Exposure | Earned Premium at Current Rates | Ultimate Loss |
---|---|---|---|---|
A | 1 | 4,000 | 500,000 | 425,000 |
B | 1.2 | 2,500 | 375,000 | 350,000 |
C | 1.125 | 1,000 | 140,625 | 100,000 |
Suppose the following is true:
- Policies are annual.
- Loss cost inflation is 4% per annum.
- The insurer is targeting an 12% overall increase in rates.
Using the loss ratio method, determine the new rates, effective for calendar year 3, for region C.
- 124.55
- 128.66
- 130
- 137.25
- 155.4
According to the loss ratio method, the indicated differential change factor for region [math]i[/math] equals the projected loss ratio for region [math]i[/math] divided by the projected loss ratio for the base level:
Region [math]i[/math] | [math]R_{i,I}/R_{i,C}[/math] | [math]R_{i,I} [/math] |
---|---|---|
A | 1 | 1 |
B | 1.098 | 1.3176 |
C | 0.8366 | 0.9412 |
Given a targeted overall change factor of 1.12, the indicated change factor for the base rate equals
Hence the base rate should be increased by 10.5%. The earned premium at current rates for region A's accident year 1 equals $500,000 with an exposure of 4,000; therefore, the current base rate is $125 per exposure unit. Since we have the current base rate, we can derive the rates for each region using the indicated rate differentials derived above:
Region | New Rate per Exposure Unit |
---|---|
A | $138.13 |
B | $182 |
C | $130 |