Hey all,

I have a 1500+ row spreadsheet detailing cellphone billing data for my institution over the past five years, and column A is the billing month/year while column B has the cell number, and col. C has the billing charge, and so on.

What I want to do is make a chart detailing the total count of actual cellphones in use each month from the start of the data to the present. Obviously some numbers have multiple entries each month for different charges and billing plans. So how do I get excel to count the unique numbers for each month and give me total cellphones for each month? I tried putting cols. A and B into a pivotchart but it counts the number of entries and not the unique cellphone numbers. Any ideas?