I have a spreadsheet that has City in column A, and customer # in column B,
and a invoice number in column C, It is sorted by column A, then column B.
I need to count the number of invoices in column C for each customer in
column B and for each City in column A.

I tried the data subtotal function to count C at each change in column B,
which Counts number of customer invoices, but I also need to know for each
city (col A) how many invoices each customer had.

Sorry to be so wordy. Any Suggestions