I need one help too :)

I want to find number of "yes" in both columns but if yes is in both columns
it should be counted as 1

for example
A B
yes no
no yes
yes no
no yes
yes yes

The answer should be 5
I tried the formula =SUMPRODUCT((A1:A5="Yes")*OR(B1:B5="YES")) but its not
giving me the right answer, its giving me 3. Can any body please tell me it
in Sumproduct form as I have to compile the resuolt with other columns too