This seems a little like the 'measure with a micrometer and cut it with a meat ax' discussion. First one of those disclosures, 'I don't depend on SWR for retirement.' However, I do have IRA's and such and do want to know what I can draw out and have them last my entire retirement.
Having said that, and reading much about the SWR on this board and other placed, it is just not that accurate of a forecast. If I understand it, which may be the problem, it is initial amount and rate you can withdraw from your savings increasing each year for inflation. If this amount is set for the initial withdrawal then the amount is key not necessarily the rate for future withdrawals. I know many on this board manage the rate depending on what their portfolio does, however, IMHO, in those cases you are not really using a SWR, and that makes perfectly good since. Running out of cash at 89 is not a option for most of us.
If the SWR is truly a valid number, then it should not make any difference when you calculate it. It has never made since to me that an investor that retires on Jan 1 with 1,000,000 can withdraw 40,000, however, if he retires one year later with 500,000, he can only withdraw 20,000. According to SWR theory he will withdraw 40,000 plus inflation from his 500,000 portfolio in his second year. If the reason for his portfolio drop is 'economic' i.e. he did not take out 500,000 to purchase something or such, then it seems to me he is in the same place the second year.
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