Hi all,

I have 24,000+ records in my spreadsheet, all originating from the
same database. It would seem that this database has a mind of its'
own when it comes to producing date and time fields.

Background, I am trying to calculate the working days and hours
between two date cells. The formula I am using was provided by good
people on this group. It is:

=((NETWORKDAYS(H2,I2)-1)*("17:00"-"08:00")+MOD(I2,1)-MOD(H2,1))*24

(answer 1.5
where H2 = 13-09-2009 2:00 PM
and I2 = 13-09-2009 3:30 PM
)

However, and no matter how I try and work this out, there are results
in other fields that show as negative! Now the times are based upon
road trips; booking out the vehicle, then booking it back in! The
database won't let you book a vehicle back in before it left,
obviously. So, my problem is, why do I get negative values for some
calcs, and not others? I hope it's a formatting thing, but I cannot
work out how to get the consistency across all the cells

Any help would be appreciated!

Pete