Count entries per user?

I found the count function: count(formname[<expression>])
but it doesn't say how you count entries for each collaborator
as in
count(formname[<collaborator1>])

so as to get for instance:
User 1 in October: 75 entries
User 2 in October: 72 Entries
User 3 in October: 57 Entries

And so on...

This could be useful for DB and Reports after
extraction from Zoho Creator App...