When you type a formula in Openbox, it can refer to calculations or inputs that aren’t in the model yet. But they need to be in the model, and so Openbox will offer to add them for you.

You can say no, but they will be added as placeholders at the next validation. Otherwise, there would be the equivalent of #REF errors in the Openbox model.

Openbox will also ask if you want these new calculations/ inputs to be series or constant items. If you tell it not to ask again, it will assume they are all series in future.