Blank if non-numerical

[ChaosPup]

Hi all,

I am creating a simple Overtime Planner to calculate planned v actual hours. At the moment, I can type in the planned start/finish times and it will give the extra hours. Easy. If either the start or finish time cells are blank the OT cell stays blank. I'm using this formula -

=IF(ISBLANK(E4)," ",IF(ISBLANK(F4)," ",(F4-E4)-$U$4))

where E4 and F4 are the start and finish times, and U4 is the core hours so I can calculate OT. However....I also need to include non-numerical entries (H and S) - what can I add into the formula to leave the OT cell blank if either E4 or F4 are non-numerical? I tried adding an (IF(ISNUMBER)) argument but I get a 'too many arguments' error.

Thanks!

 

[RoryA]

You could use:

=IF(COUNT(E4:F4)<2," ",(F4-E4)-$U$4)