I have 3 columns (A:C) - header names are PatientID, Reason, Paid
Reason is the reason for the visit, Paid shows if the visit has been paid for. So the data looks like this:
192837 Reason1 Y
459357 Reason2 Y
459379 Reason2 Y
192837 Reason1 Y
459357 Reason2 Y
342873 Reason3 N
345035 Reason2 N...