8. A pension plan is obligated to make disbursements of $1 million, $2 million, and $1 million at the end of each of the next three years, respectively. Find the duration of the plan's obligations if the interest rate is 10% annually. If the level of interest rates goes down by 50 basis points (one basis point is 0.01%), how much do you expect the pension plan's obligation to go up (in percentage terms)