How to join two functions in a formula?

[Suzanne]

I am currently using a formula which calculates a rolling total days to turn
around a widget from receipt of component parts, but this gives me the total
number of days. I want the formula extended to use the Excel Function
NETWORKDAYS as well as a National Holiday chart that I have. How do I do
this?

The current formula is =IF($Q2-$O2<0,TODAY()-$O2,"")

 

[JE McGimpsey]

One way:

=IF($Q2<$O2,NETWORKDAYS($O2,TODAY(),holidays)-1,"")