Causal has "goal seek" functionality similar to Excel, however please note that the functionality is currently fairly limited / manual. You can access Goal Seek from the context menu (by right-clicking on a variable).
You must set a sensible range for the input variable/s, and then whether you want the output variable to be equal to a specific number, or be maximized/minimized.
The current limitations of Goal Seek are:
Causal doesn’t automatically output the "goal-seeked" value anywhere, it just generates the value for you in the modal on-screen, for you to then hardcode manually into your input variable/s.
Goal Seek is restricted to constant values (not time series values). If you wish to use Goal Seek for time series values, you must Goal Seek for one time period at a time.
The variable that is the "input" value in the Goal Seek must be in the Inputs section of the model.
We are planning on improving Goal Seek in the coming months - so stay tuned