Forecasts
A Cost Explorer forecast projects your recent average daily spending over a future period of up to 90 days.
A forecast estimates what a project is going to spend over a future period if it keeps spending at its recent rate. Cost Explorer averages the daily cost over a lookback period, 7 days unless you choose otherwise, and projects that average forward.
For example, if a project spent 245 over the last 7 days, its average is 35 a day, and the forecast for the next 30 days is 1050.
A forecast is a straight-line estimate, so:
- It does not know about resources you are about to create or delete.
- It does not follow trends: a project whose spending is growing is under-forecast.
- It does not account for price changes or seasonal patterns.
- It forecasts zero for a project with no spending in the lookback period.
Choosing a lookback
A longer lookback smooths out one-off spikes, such as a large test that ran for a day. A shorter one reacts faster when you add or remove resources. The lookback can be from 1 to 90 days.
Forecasts and budgets
To be alerted when a month is on course to cost more than you expect, use a budget with a forecasted threshold instead of checking forecasts yourself. Budgets projects the spending so far in the current window to its end.