What do you have in cells D5, D7, D9 and I5, I7, I9 etc? If these are
blank then you could just use:

=AVERAGE(D4:D16,I4:I16)

as the function will ignore any blank cells. Do you have formulae in
the cells D4, D6, D8 etc which return a value, or do you type these
values in yourself?

Hope this helps.

Pete

On Jul 29, 9:49*pm, Colin Hayes wrote:
HI

I have a puzzle - I wonder if anyone can assist.

In cells *D4,D6,D8,D12,D14 and D16 in have formula-based totals for the
first 6 months of the year. In the equivalent cells in column I I have
the totals for the last 6 months.

I want to have , in cell G17 , a running monthly average for the year so
far.

It needs to divide the overall total thus far with the number of months
used up so far. Clearly , months that are still zero should not be
counted until they have content as this would skew the average.

Can anyone help with a formula for G17?

Any advice gratefully received.

Best Wishes