This is very helpful indeed. I think I see how it works. What's "Wend"
mean?

It's nothing like what I expected. I didn't know about
"Worksheets.Count." Nor that you could refer to sheets  by number. I
had the idea  one would use MoveLast somehow, with something like
"Activesheet.MoveLast," although that doesn't work. Then MoveLeft, use
y = BOF, MoveRight. If y = False run  format1, if y = True run format2.
Was I even in the ballpark?

Anyhow, this does the trick, I'm sure. I haven't tried it yet, but
I'll do that next. For a refinement, let me ask you if there's a way
to test if the active worksheet contains any text? And if not, delete
it instead of running either of the format  macros?

God, I've got a lot to learn. I didn't even know Sheets existed, and
I'm still shaky about its syntax. Where can I find exhaustive lists of
the commands, recordsets, and so forth, available? I've several books
and none of them really has that.