In Column A are the employees' names. The employee's name could be in the
column numerous times. Each employee belongs to a district, which is in
column B. So if name is John and it appears five times, then in cell C2, I
want to display 1. If there is another employee, Judy for instance that
appears 3 times, then in cell C2, I want to put 2, because there are 2 unique
names.

Can anyone help me with this formula?

Thanks in advance.