Jim: each year to sell 4% of the number of shares you still own that year.

I think the 4% rule is for the typical retiree, needing a simple and easily executable rule of thumb, not for people who spend half their lives on the Berkshire board, discussing in detail this and that and trying to come up with the most efficient technique, no matter how complex that might be.

And if your portfolio consists not practically only of Berkshire shares contains a bouquet of shares and index funds "selling each year 4% of the number of shares you own that year" IS complex for people who still have a life away from such boards.

I personally once made a complex Excel sheet, projecting my route until the statistically probable end of my life + 10-20 years, with the usual variables as input (inflation, interest rates, expenses; maybe others too, I don't know, haven't looked at it since years), with two scenarios for the largest expense, house (renting vs. buying) - - - but hey, how many people have the time on their hands - and the inclination - to do so?

I didn't know then about that simple "4% SWR" rule, but think it's far more suitable for most retirees than whatever sophisticated scheme this board comes up with, actually think it's brilliant to have such a simple rule of thumb!

And since the average retiree's SOR is better than the historical worst, they end with a portfolio something like 2.8X their initial balance, they WR more once past SORR.

Maybe that's why our boss says 5% (instead of 4%)?