I am 31 years old and have $30,000 in savings. I plan on saving $1,000 per month until I retire at age 68. I'm of the opinion that I can make 9% on my investments. If the actuaries say that I will live to be 94,and I shift my post-retirement savings to a safer portfolio that delivers a 4% return, how much can I take each month from my portfolio and end up with exactly no money when my time is up?