Description: Calculates averages over blocks of N cells. When
there are M values in the range, M/N averages are
calculated, for each block of N values an average is computed
and returned.

BlockAverage is an array function, it returns more than one value.
Select a range of cells, one column and more than one row. Enter the
formula and press Ctrl Shift Enter simultaneously. This will create the
array function in Excel.

Example: Calculation of 20 block averages. Block size
is 5. The first value is the average of A1:A5, the second value is the
average of A6:A10, etc. =BlockAverage(A1:A100,5)