Sum Every Second Row
The formulas in the following examples return a sum of every second row in a range of cells. In the first example, the summing starts with the first row, whereas the summing in the second example starts with the second row.
Starting With the First Row
The following formula returns the sum of every second row in A2:A10, starting with the first row...
=SUMPRODUCT(--(MOD(ROW(A2:A10)-ROW(A2)+0,2)=0),A2:A10)
Based on the sample data, the formula returns 150.
Sample Workbook: Download
Starting With the Second Row
The following formula returns the sum of every second row in A2:A10, starting with the second row...
=SUMPRODUCT(--(MOD(ROW(A2:A10)-ROW(A2)+1,2)=0),A2:A10)
Based on the sample data, the formula returns 220.
Sample Workbook: Download