Hi Daffodil,
Thank you very much for the suggestion, however, it doesn't count unique Names, so if it sees multiple AA in my example xls it counts each of them.

The pivot table suggestion also doesn't count unique values. I understand that Excel 2013 does provide the ability to show unique counts, however, it won't let me group the dates by months so I can't see how many unique names show up for each month.

If it's more simple I would be happy to simply see:
Month Count
Jan 2013 3
Feb 2013 6
Mar 2013 3

Etc.

Open to any other suggestions.