Dear Financial Adviser,

My spouse and I are each $62$ and hope to retire in three years. After retirement we will receive $$7,600$ per month after taxes from our employers$$ pension plans and $$1,600$ per month after taxes from Social Security. Unfortunately our monthly living expenses are $$15,100.$ Our social obligations preclude further economies.

We have $$1,010,000$ invested in a high$-$grade, tax$-$free municipal$-$bond mutual fund. The return on the fund is $4\mathrm{.}0\%$ per year. We plan to make annual withdrawals from the mutual fund to cover the difference between our pension and Social Security income and our living expenses.

Sincerely,

Luxury Challenged

Marblehead, MA

You can assume that the withdrawals $($one per year$)$ will sit in a checking account $($no interest$)$ until spent. The couple will use the account to cover the monthly shortfalls.

How many years before Luxury Challenged runs out of money?

Note: Do not round intermediate calculations. Round your answer to $2$ decimal places.