How to set words target for a Folder?

I know how to set target for documents.

But I’d like to set words target for a folder (including many sub-documents),

is there any method to do that?

P.S. English is not my mother tongue, please try to understand my words,

thank you!

I put several books in one project for a series, and project targets apply to the currently selected Compile Group. You might use that to get what you want.

Some options from Sec. 20.1.2 of the manual:

Déjà vu…,