countif ?

[katagrga]

I am trying to find the number subtotals that have a duplicate date within
them.
I have the info subtotaled by name. The answer I need from the example
below is 4. I appreciate your suggestions.

A B
Alex Jones 1/2/08
Alex Jones 1/2/08
Alex Jones 3/4/08
4
Ben Jackson 5/1/09
Ben Jackson 5/12/09
2
Craig Meyer 7/2/08
Craig Meyer 7/2/08
2
Dan Smith 3/15/09
Dan Smith 3/24/09
Dan Smith 3/24/09
Dan Smith 5/7/09
Dan Smith 5/7/09
Dan Smith 5/7/09
6
Eric Roberts 4/6/09
Eric Roberts 4/6/09
Eric Roberts 5/17/09
3

 

[katagrga]

Anyone out there have any ideas how I can get this information? I need a
count of the number of customers who wrote bad checks that wrote them on the
same date. So of the customers with bad checks how many had more than one
check written on the same date. Please help!