How to COUNT records in Pivot Table?

I need to summarise a past due aging report in Excel 2010 which has data for receivable balances of about 200 customers. Available info in a Worksheet includes Customer #, Name, Balance, Security, Provision Amount, Aging Group (0 days, 30 days, 90 days, 365 days etc.), Category ( On time, past due, loss etc.)

I have tried to create a simple pivot table that shows the following:

Aging category (30 days, 60 days, 180 days etc.), Total Balance of each category, Total Provision for each category, and number of customers in each category.

I cannot bring in a column that gives COUNT of number of customers for each aging category. How do I do it? Please help and oblige, and be simple plz (no VBA etc. required).