In Column C of my spreadhseet I have a listing of elapsed days (the
difference between a date established in Column A and Column B (where column
A is a discharge date, and column B is the file closing date). Below is the
formula which exists in Column C, and it works just fine:

=DATEDIF(MIN(A4,B4),MAX(A4,B4),"D"))

I am also using the average function (=AVERAGE) to calculate the average
days between discharge date, and file closing (identified in Column C) for
all clients, which also works just fine, and gives me information about the
"average" closing of files (from discharge to closing) on all client cases
posted on the spread sheet:

=AVERAGE(C4:C500)

For enhanced clarity in my overall analysis of data, I would also like to
use the "average" function to obtain information by "progam" and by
"counselor". For formula purposes, "Elapsed Days" are identified in Column C,
"Program" type is listed in Column F, and "Counselor" is listed in Column G.
The following are the formula outcomes by counselor and program that I'd like
to obtain:

1) What are the average days between discharge and file closing by program?
2) What are the average days between discharge and file closing by counselor?

I'll assume that the above 2 are "array" formulas, but I couldn't wrap
myself around how it should look with use of the "average" functcion. Perhaps
something like the following (which I got an error value for):

=Average(C4:C500)*(F4:F500,"OP")
=Average(C4:C500)*(F4:F500,"Jen")

The first formula above should provide the outcome by our various programs
(OP,TP,ARC,IOP), and the second formula should provide outcomes by the
various counselors (Jen, Ernest, Lynn, etc).

Any help would be appreciated!
Thanks in Advance,

Dan