Formula to extrapolate dates

Hello

I have some data that is in months, quarters and years. I have extrapolated the data out so that I know which months in which quarters and years it fits into. I now need to fit those months into the respective month and average out where there are over laps.

See the attached spreadsheet. For example Row 7 contains values that will overlap with some of the rows above it. What I need to do is first put the value in column N for cell A3 and A7 into the April month below and then average the two.

I need this to be automated so that it will look in each cell from A2 to L11 and fit them into the dates below.

Thanks
Ed

So in N16, you want 111.5? (120 + 103)/2 If not, can you give a specific result, naming cells, variables and results?

Edit: Actually N16 is 2012, you would want that result in B16, yes?

If my assumptions above are correct, then in A16, dragged to the right, try

=SUMPRODUCT(--($A$2:$M$11=A$15)*$N$2:$N$11)/SUMPRODUCT(--($A$2:$M$11=A$15))

Does that work for you?

See attached.