Question : How do I keep a running sum on a form in Access 2003?

I have a simple form in Access with two bound fields: "StartTime" and "EndTime".  There is one unbound field called, "TimeSpent" whose control source is =[EndTime]-[StartTime].  These three fields are formatted as Short Time.  I would like an unbound field in the form footer that keeps a running sum of "TimeSpent".

Is there a way to do this?

Thank you and regards,
Saleve

Answer : How do I keep a running sum on a form in Access 2003?

Add a textbox with a controlsource of
=Sum(=[EndTime]-[StartTime])