I expect to be retired for about 18 years (216 months). I expect to earn 6% APR compounded monthly (after-tax) on my investments during my retirement years and I also expect inflation to average about 2.4% annually (compounded monthly). How much do I need to have saved to be able to spend the equivalent of $10,000 per month during each month of my retirement (note that the $10,000 will increase each month to keep my purchasing power at $10,000 in today's dollars)?