How do I create a formula that gives me a cumulative average each week, over
a 40 week period?

Not exactly sure what you mean. If your weekly data starts in A1 and
goes to A40, enter this formula in cell B1 then copy down. Note the
absolute references on one half of the formula.

B1 =Average($A$1:A1)

- John

Well, let me explain....we recently began keeping attendance during church
worship services at our church and I have created a worksheet that we can
input the info in and it will total it at the bottom of the sheet. I have
allowed for about 40 weeks of input but we are only on week four. What I
would like to do is have a formula under the cell for total that would let me
see what our average number is in the worship services.

"John Michl" wrote:

Not exactly sure what you mean. If your weekly data starts in A1 and
goes to A40, enter this formula in cell B1 then copy down. Note the
absolute references on one half of the formula.

B1 =Average($A$1:A1)

- John