The cost of a life insurance policy is determined by two things: the guaranteed benefit amount and the individual risk of the policyholder. The latter is more complicated, and includes many factors, including health, age, and occupation.
As of May 2017, a 30-year-old woman purchasing a 20-year, $250,000 term life policy can expect to pay about $141 per year. For comparison, a 60-year-old woman purchasing the same policy can expect to pay $1,033 per year.
Since women have longer life expectancy on average than men, the latter can expect to pay slightly more. The same 20-year, $250,000 term policy will cost a 30-year-old man $156 per year on average.