Exercise
You are given the following earned premiums for three calendar years:
Calendar Year | Earned Premium |
CY5 | 7,706 |
CY6 | 9,200 |
CY7 | 10,250 |
All policies have a one-year term and policy issues are uniformly distributed through each year.
The following rate changes have occurred:
Date | Rate Change |
July 1, CY3 | + 7% |
Nov. 15, CY5 | – 4% |
October 1, CY6 | + 5% |
Rates are currently at the level set on October 1, CY6.
Calculate the earned premium at the current rate level for CY6.
- 9300
- 9400
- 9500
- 9600
- 9700
Key: C
Let P be the premium after the July 1, CY3 rate change. On November 15, CY5 the premium is 0.96P and on October 1, CY6 it becomes 1.05(0.96)P = 1.008P. The relevant parallelogram is:
The upper left triangle for CY6 has area (1/2)(7/8)2 = 49/128 and the lower right triangle has area (1/2)(1/4)2 = 4/128. The weighted average is [49 + 4(1.008) + 75(0.960)]P/128 = 0.9768P. The current premium is 9200(1.008)/(0.9768) = 9494.