Multi-driver forecasting
A forecast amount can be computed from several inputs at once with a formula. You declare named drivers, each either a single value or a per-period series, and write a formula over them. This goes beyond a variable amount (one series you supply) and a derived amount (one basis times a rate): a formula composes multiple drivers with arithmetic, so a revenue line can be units times price minus a per-unit fee, each of which can move independently.
How to use it
- On a forecast definition, set the amount method to driver formula.
- Declare each driver by name and give it a value or a per-period series.
- Write the formula in terms of those driver names, for example
units * price - units * fee. - Generate: each occurrence's amount is the formula evaluated on that period's driver values, and it drills to show the drivers and the numbers used (see *Provenance drill-down*).
The safe formula boundary
The formula is parsed into a restricted syntax tree that allows only arithmetic and references to the drivers you declared. A name that is not a declared driver, a function call, or any other construct is rejected when you save the definition, not at generation time. So a formula can never run arbitrary code; it can only combine your drivers with math. This is the same restricted-tree boundary the plugin framework uses (see *Plugins: forecast engines and import parsers*).
A definition that does not use the formula method is unchanged; multi-driver forecasting is opt-in per definition.
In-app documentation, version 5. Generated from the product documentation source, so this matches the app exactly.