Subject: Re: Berkshire Safe Withdrawl Rate
How about this as a fairly simple method. I already have a running 5-groves IV calculation (similar to Jim's 2 and a half column, I think).

5 Groves IV/share 2020 $280, inflated to 2026 $332
5 Groves IV/share 2025 $446
Real IV Growth CAGR =((446/332)^(1/5)-1) = 6.1%
Safety Margin 1%
IV % to withdraw 5.1%
Withdrawal Amount $22.66/share owned
Withdrawal Rate of 4.5% at $505/share