The traditional studies (incorrectly) claimed a 30 - year safe withdrawal rate of 4 % of a portfolio's initial balance (plus inflation). (early-retirement-planning-insights.com)
I'm serious enough about retirement that I started doing a lot of research on safe withdrawal rates and withdrawal strategies, see here. (thegreenswan.org)
The average safe withdrawal rate for all those 200 + retirees is, believe it or not, 7 %! (moneyboss.com)