What it is
Revenue churn (dollar churn) is ARR lost when customers cancel — and, if your policy says so, when they contract. It is the dollar view that feeds GRR.
How it’s calculated
Sum ARR removed for churn events in the period ÷ starting ARR. Keep contraction on its own waterfall line unless you explicitly define “gross churn” to include both.
Where it breaks
Revenue churn breaks when partial downgrades are mislabeled, when credits and true-ups distort the period, or when FX and entity moves look like churn.
In the board pack
Present revenue churn beside logo churn and GRR. The waterfall should prove the dollars.
Keep the written definition stable across close, the board pack, and diligence so the same word never means two math models.
When this metric moves, point to the source schedule and the bridge components — not a screenshot from a private workbook.