With
A1: 2/4/1900 4:25:57 PM......displayed as 856:25:57
B1: 1257

Regardless of the display format....Excel stores the
date/time values as a number
with digits to the left of the decimal point = days
and digits to the right of the decimal point = decimal fractions of a day.
The actual decimal value of cell A1 is: 35.6846875

Consequently, this formula returns the production per hour:
=B1/(A1*24)

In the above example, the formula returns 1.46771636994159 (per hour)

Does that help?
--------------------------

Regards,

Ron
Microsoft MVP (Excel)
(XL2003, Win XP)

"Taylor" wrote in message
...
I'm presented with time in [h]:mm:ss format, ie. 856:25:57, and with a
total
productivity number, ie. 1257. Is there a formula to calculate how many
per
hour, given this format? If not, what is the best way to convert that
cumulative time into a decimal?