I have four columns: StartDate, StartTime, EndDate, and EndTime. This
represents the timed duration of several washing machines used in a
continuing fashion. I want to calculate the total time the washers are
in use so I can figure out when they were not in use. This eludes me
because some of the dates/times overlap. Can someone help with me
calculate to total in use time?

ColumnA ColumnB ColumnC ColumnD
StartDate EndDate EndDate EndTime
1/21/2008 10:00 1/22/2008 9:30
1/21/2008 10:20 1/31/2008 10:30
1/23/2008 17:00 1/25/2008 9:30
1/23/2008 17:05 1/28/2008 9:15
1/24/2008 12:00 1/24/2008 13:00
1/25/2008 9:29 1/25/2008 11:52
1/25/2008 15:00 1/29/2008 6:30
1/25/2008 15:15 1/25/2008 16:30
1/30/2008 12:15 2/1/2008 16:45
1/31/2008 16:15 1/31/2008 17:30
2/4/2008 14:30 2/5/2008 12:45
2/4/2008 14:30 2/4/2008 15:45
2/5/2008 12:30 2/7/2008 13:15
2/8/2008 12:15 2/8/2008 12:50
2/11/2008 8:00 2/11/2008 13:10
2/11/2008 13:30 2/11/2008 14:30




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Steve Gilley