It's interesting the different "opinions" on definition/calculation of WR. Yes, I know there is the "standard" or Norm.
To me it's not 'interesting', it is frustrating and counter-productive.
If we are to have meaningful, productive discussions, we have to agree on the meaning of words. As the old saying goes, you are entitled to your own opinion, but you are not entitled to your own facts.
To be useful, we must consider "withdrawal" to mean funds removed from your portfolio (spent or given away). Not transferred to another fund. If you want to get into the weeds on this, I suppose there may be rare cases where a large purchase was made for a non-consumable asset that could reasonably be sold at a later date. In that case, the current sale value could be considered part of your liquid portfolio.
For consistency, the denominator is your start of year (or 12 month period) liquid portfolio value.
Your portfolio performance has nothing to do with "Withdrawal Rate" until next year's calculation, where you use the new portfolio value.
That takes more effort to put into words than it takes to just do it. We have two places where money leaves. If I sum up the debits for the year, not including any money transferred to another account (that's not 'spent', just moved), divide by my total portfolio value at the start of the year as a percent, that's it.
Any other calculation is something different, and is not apples-apples to "Withdrawal Rate".
I'm not sure what to call it, but if I take the difference between my YE 2024 Portfolio balance and my YE 2025 Portfolio Balance (numerator) and use the YE 2024 as denominator, the change was -3.0%. This would include changes in value of Portfolio due to Div's, Cap gains/(losses), etc.
Flieger
That is just what it is - the change in your portfolio value. Without going deeper, we have no clue as to the components that make that up (gains/losses, spending). It's a useful thing to track, but it is separate from WR and separate from portfolio performance. You could be up because gains exceeded losses and spend, you could be down because of losses and spend, or down because spend exceeded gains.