Forecast, Budgets & Anomalies

Plan covers the forward-looking half of cost management.

Forecast: three numbers, not one

The forecast reports a low, an expected and a high figure.

A single forecast line is false precision — it is wrong every month, and being wrong every month is how a forecast stops being read. A band communicates what a forecast actually knows, and a period that lands outside it is genuinely informative rather than routine.

Budgets

Budgets are tracked against the forecast and against actuals. A budget that only compares against actuals tells you about the overrun after it has happened; comparing against the forecast is what makes the warning early enough to act on.

Anomalies

Anomalies are detected against the daily cost series rather than against monthly totals — a spike that starts on the ninth and is corrected on the eleventh does not exist in a monthly figure at all.

Anomaly detection needs enough daily history to have a baseline. A newly connected account produces few useful anomalies until the series is long enough to have a shape.