summing cells in a periodic order

hi friends,
i'm looking for a solution for my problem... the situation is; i have a huge number of rows and i want to add some data like this:
A1+A6+A11+A11+A16+A21+A26+A31+A36.... and goes on with an increment of 5 cells. but inserting this to the formula bar is very time consuming. i hope there is an easy way of doing this. and i will be very glad to hear it from you. by this way i can spend the time which i gained from this job by praying for you )

thank you guys, waiting for your replies...

Try the following formula....

=SUM(IF(MOD(ROW(A1:A65000),5)=1,A1:A65000,0))

This must be entered as an array formula by typing it in then using Ctrl Shift and Enter simultaneously (so that the formula has {} braces around it).

The formula divides the row numbers by 5 and if there is a remainder of 1 (e.g. A6, A11, etc) then the contents are summed.

The formula goes up to row 65,000 which should be plenty.

(Techie note: it doesn't seem to work by simply specifying the whole column e.g using A:A)

Rats! Pipped to the answer by Carim!

thank you very much guys, that looks pretty good...

that fixed the problem with a few corrections
also the method gave me an insight and spreaded the solution to other problems )

i'm new on the forum, and i liked it very much... you are doing a very good job

Originally Posted by Carim

Glad it fixed your problem ...

Thanks for the feedback