yogi_Compute A Set Of Value With Intermediate Average Values

Yogi Anand, D.Eng, P.E.                                         Google Spreadsheet                            www.energyefficientbuild.com

laurentJ said:
Complete a set of value with intermediate average values
I have a set of value that are generated automatically in a column after a sort and a unique function. I want to be able to sample that data with intermediate average values.
For example I have in the column B
2
4
6
8
And I would like to have in column C
2
3 = (2+4)/2
4
5 = (4+6)/2
6
7 = (6+8)/2
8
Problem is that I want to column to be dynamic and I do not want to enter manually those formulas in every two cells.
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