Countif with a critera then filtered

Hi

Trying to get my countif formula to work when I filter certain cells. At the moment the countif is counting the entire spreadsheet against a criteria which is fine, but when I filter I want the total to reflect the visible cells and obviously once I clear the filter it will go back to the grand total.

I have a roster with employees names, supervisor and other information and continuous dates running across the top of the sheet till end of next year.

So when I filtered for N on todays date I get 8 which is correct (Example 1) but then i want to narrow the search down to by a certain supervisor, so I select supervisor 1. So I should get 3 employees on Night-shift working under Supervisor 1 (Example 2)

The formulas I have at the moment are:
Dayshift employees
=COUNTIF(AAC$7:AAC$212,"1")
& nightshift employees
=COUNTIF(AAC$7:AAC$212,"N")

Hopefully this makes sense

Any help on this would be great appreciated