Assuming you have column headers (such as given in your example)
In column D1, enter formula:
=(A2+B2)-(A$2+B$2)
Drag down to fill column
Format Customized [mm]
HTH
--
AP
"Jerome Ranch" <(E-Mail Removed)> a écrit dans le message de news:
(E-Mail Removed)...
>I have data that I take over time (several days).
> I want to calculate total elapsed time over all the days of the
> experiment.
>
> Time data may look like this
>
> date time data elapsed time (min)
> 5/12/2006 09:10:00 1 0
> 5/12/2006 10:40:00 200 90
> 5/12/2006 12:30:00 etc 200
> 5/12/2006 15:30:00 380
> 5/12/2006 17:00:00 470
> 5/12/2006 20:45:00 695 ( I get this far with but
> when a day changes, how might I calc this)
> 5/13/2006 07:30:00
> 5/13/2006 10:40:00
> 5/13/2006 12:30:00
> 5/13/2006 15:30:00
> 5/14/2006 10:40:00
> 5/14/2006 12:30:00
> 5/14/2006 15:30:00
>
>
> Knowing elapsed hrs I can calc minutes by mutiplying hrs*24*60.
> So how might I build the logic with formulas to accompish this?
>
>
> Thanks
> Jerry