This is what I'm currently using which is not working:

=AVERAGEIFS(C1:C100,B1:B100,">=H2",B1:B100,"<=I2")

where the C column is the value that i want averaged for each day. (600-800 range)

where the B column is the date column corresponding to each C value. (21-Jan-08 format)

where the H column is the beginning date of each project. (same format as above)

where the I column is the end date for each project. (same format as above)

any ideas?