One way

=SUMPRODUCT(--(MOD(ROW(A1:A100),2)=1),A1:A100)

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Regards,

Peo Sjoblom

(No private emails please)


"Sarah needs to know" <Sarah needs to wrote
in message ...
I have a list of numbers all in one column and I want to be able to type in
a
formula that will SUM the numbers in every second cell only, without
having
to click on each cell individually. This is how I do it now,
=sum(a1+a3+a5+a7+a9+....etc). Is there a formula that will tell excel to
do
this automattically? If so can you tell me how to do it?