I have a list of referrals which includes date of appointment, status (e.g.
urgent, non-urgent etc.), appointment date, waiting time (number of days
from appointment received to appointment date). Thanks to help already
received I can count the number of referrals received in a month/year that
match a particular status. What I would like to do now is find the average
waiting times for that month/year. For a start Ive been trying to sum the
waiting time days using variations of the following:

SUMPRODUCT(--MONTH(Referrals!$C$4:$C$1200)=MONTH(B$2),
--YEAR(Referrals!$C$4:$C$1200)=YEAR(B$2),--(Referrals!$E$4:$E$1200=€�urgent€�),
Referrals!$I$4:$I$1200)

C:C is the appointment received date, B2 is the month/year on the statistics
sheet, E:E contains the status, and I:I the waiting time in days.

Other versions of this formula resulted in blithering idiot messages but
this one politely returns 0 which I know is wrong. Any help would be
appreciated.