You are endowed with $5,000 of after-tax cash and 20-year investment horizon. You have a marginal tax rate of 40% and you expect to face the same rate over the next 20 years. You expect that investing passively in an index fund will generate a 10% return each year, pretax, for the next 20 years

The future value of a $1 investment for 20 periods is as follows:

R		Factor
6%		3.207
8%		4.661
10%		6.728
12%		9.646
14%		13.744

You choose to learn tax planning and invest passively. You invest in a 401(k) account (or similar tax-deferred vehicle) such that the after-tax cash cost of the investment is $5,000. What is the after-tax future value of your investment?