=SUMPRODUCT(COUNTIF(INDIRECT("'"&ROW(INDIRECT("1:1 5"))&"'!B51"),{"Y","N"}))

--
HTH

Bob Phillips

(remove nothere from email address if mailing direct)

"ferde" wrote in message
...
I have been trying to use the countif function to count the number of
times a
"Y" response occurs in a specific cell in 15 different worksheets that
are
all in one workbook. ... I have tried
=SUM(COUNTIF('1:15'!B51,{"Y","N"}) but I keep on getting a "value
error".
This formula works in one worksheet but it wont count multiple
worksheets.
I've been trying to solve this for days by myself but I'm stuck. I'm a
new
user and really would appreciate any help.

Thank you