[almost_usual]

I’m not sure they’re considering inflation as well.

A safe withdrawal rate would be like annual rate of return - annual inflation - 1% safety buffer.

So 4% - 2% (target inflation rate) - 1% (buffer) = 1%.

If you don’t include the 1% buffer here you have no margin of safety for a market downturn.

[AbeBW]

The 4% figure comes from something called "The Trinity Study" and most definitely considers inflation.

For more information about safe withdrawal rates then you probably want see https://earlyretirementnow.com/safe-withdrawal-rate-series/