I have created an Excel workbook containing several tabs. The workbook is to
keep track of a project for a social organization, Flags for Patriotism
Program. Briefly, the Flags Program posts American Flags at participating
businesses on specific holidays throughout the year. The entire project is
divided into 6 routes (A-F).

As such, I have a tab for each route. Other than the business names and
addresses, the tabs are identical to start. The user enters the name(s) of
the people that post a route into cells A4, K4, A5, and K5 (room for 4
names). Often times, one person will post more than one route.

On a "Summary" tab, I need to count the people that were involved in the
process. However, if I posted 2 of the routes, it counts me as 2 people and
lists my name twice. How can I get it to count me and list my name only one
time in a certain field on the "Summary" tab, say cell BW6?