Thanks AliGW -- message understood!!

In answer you your query the latest Book 2 file may be better to understand the request. The 'markers' 1,2,3 etc can be found in column A as 11, 12, 13 etc.... I have also tried to use the 'markers (in column N to attempt to write a formula). As you may notice I have used them to reproduce the last value in each block. Now I am trying to do the same for 'averaging'. each block (in column N). ie B1 should have the average for N4:N8; B2 have the average for N12:N15; B3 the average for N19:N20; B4 the average of N24:N28.

Thanks again AliGW

Chris