Bit confused by your formula, but in principle you can use

=SUMPRODUCT(--(A10:A27=C10),--(A10:A27<C11),B10:B27)/SUMPRODUCT(--(A10:A27
=C10),--(A10:A27<C11))

which (may) translate to

=SUMPRODUCT(--(A1:A5000=time1),--(A1:A5000<time2),C1:C5000)/SUMPRODUCT(--(A
1:A5000=time1),--(A1:A5000<time2))

in your example
--
HTH

Bob Phillips

"Miguel" wrote in message
...
I have two columns one is time and the other force values. I want to look
for
two diferent times and get the average of the forces in that range of
time. I
thought I could generalize this for several spreedsheets that I have. I
believe if I use the MATCH function to get the row position of the
different
times and then simply use the average function with MATCH may work
straight
away. I get a problem because the format average somehow does not
recognice
MATCH. For instance my formule looks like:

forceaverage=AVERAGE(RMATCH(time1,R1C1:R5000C1,0)C 3:RMATCH(time2,R1C1:R5000C
1,0)C3).
time1 and time2 are my time values and R is row and C is column (the
absolute format used by excel). C3 is the column were the forces are. C1
is
the column of the time.R5000 is the last row value.