Forecast Drift Rate
Definition
Evaluates how cloud infrastructure forecasts change over time due to various factors such as priority shifts, workload variations, rightsizing, and CUD impacts. Though percentage variance is prioritized, measuring in dollars is also valuable. Organizations set their own standards for acceptable variances.
Formula, as published
((New Forecasted Cloud Infrastructure Spend - Previous Historic Forecasted Cloud Infrastructure Spend) / Previous Forecasted Cloud Infrastructure Spend)
- Data sources:
- CSP Billing Data Organizational forecast documents
Calculate it
Example values to start with; replace them with yours.
How to measure it
How much the forecast moved since the last time you made it. Large drift with good accuracy means the forecast is tracking reality late; large drift with poor accuracy means the inputs are unstable.
More Forecasting KPIs
Definition and formula: Forecast Drift Rate, FinOps KPI library, FinOps Foundation, licensed CC BY 4.0, read 16 Oct 2026. Changed: HTML removed, dashes and British spellings changed, formula split from its data sources and examples. The calculator and the notes are Finitizer’s.
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