In: Statistics and Probability
When calculating premiums on life insurance products insurance companies often use life tables which enable the probability of a person dying in any age interval to be calculated.
The following table gives the number out of 100,000 females who are still alive during each five-year period of life between the age of 20 to 60 (inclusive):
Out of 100,000 females born
Exact age (years) Number alive at exact age
20 99,150
25 98,983
30 98,781
35 98,545
40 98,182
45 97,628
50 96,831
55 95,585
60 93,718
Suppose a 30 year old female on her 30th birthday purchases a one million dollar, five-year term life policy from an insurance company. That is, the insurance company must pay her estate $1 million if she dies within the next five years.
(a) Determine the insurance company’s expected payout on this policy.
(b) What would be the minimum you would expect the insurance company to charge her for this policy? Give a brief explanation of your answer.
(c) What would the expected payout be if the same policy were taken out by a female on her 40th birthday?
(a) Insurance company's expected payout is equal the "amount paid to the woman if the woman dies" times the "probability that the woman dies within the next 5 years".
Thus, Amount = $1,000,000
Probability = (No. of woman who died between ages 30 and 35)/(No. of woman alive at age 30)
Now, No. of woman who died between 30 and 35 = No. of woman alive at age 30 - No. of woman alive at age 35
= 98781 - 98545 = 236
Thus, Probability = 236/98781 = 0.00238912341
Thus, Expected payout = $1,000,000 * 0.00238912341 = $2389.12
(b) The minimum we expect the insurance company to charge is the expected payout calculated in part (a) ,i.e., $2389.12. This is the minimum value the insurance company needs to charge to avoid almost certain loss. This is the expected payout to the policyholder but the insurance company needs to add some contingency margin so that it doesn't suffer any losses because of the difference between observed losses and expected losses. In addition, the company needs to add the expenses incurred by them in respect of this policy because of which the actual amount charged will be significantly higher than the expected payout.
(c) The calculations are the same as in part (a) with only changes in figures during the probability calculation.
Insurance company's expected payout is equal the "amount paid to the woman if the woman dies" times the "probability that the woman dies within the next 5 years".
Thus, Amount = $1,000,000
Probability = (No. of woman who died between ages 40 and 45)/(No. of woman alive at age 40)
Now, No. of woman who died between 40 and 45 = No. of woman alive at age 40 - No. of woman alive at age 45
= 98,182 - 97,628 = 554
Thus, Probability = 554/98,182 = 0.00564258214
Thus, Expected payout = $1,000,000 * 0.00564258214 = $5642.58