So is this math about the same as seen here http://www.estimatepension.com/Retirement-Withdrawal-Calculator.aspx and putting retire age = 65, life expectancy = 95, final savings = 1,000,000, rate = 4% (7% return - 3% inflation).
That shows a yearly withdrawal of $55,605. And a 3% rate shows $49,533.
But actually that doesn't include the SS money, so not too sure now. . .
I didnt consider any interest rate when I did that just to make things a lot simpler. Honestly, I doubt many of us are going to be making a whole lot of money through interest since I would imagine that a good deal of anyone's portfolio would be in bonds. I think 3-4% interest would be a good bet. One thing that you should note though is that calculator does not seem to factor in inflation. So while I think 4% is a decent estimate before inflation, I think 7% is much too generous unless you have all your money in stocks (I defintiely don't think you should at that point).
Also, I think that calculator makes things much too neat. Since it does not take inflation into account, your standard of living/buying power will weaken every year if you take out exactly 49,533 dollars every year. that 49k will be worth a more when you are 65 than when you are 90. So while 50k every year looks good now, we really don't know how 50k will look like when we are 65 or 90.
You are right though that the calculator does not seem to factor in social security.