Troy,
Do you want a formula?
This formula will sum every nth value from the mth item in the range,
assuming in this case a range of B2:B32. Just change m and n to your values
(1 and 2 in your case), and all references to the applicable range
=SUMPRODUCT((B2:B32)*(MOD(ROW(B2:B32)-ROW(B2),n)+1=m))
--
HTH
Bob Phillips
... looking out across Poole Harbour to the Purbecks
(remove nothere from the email address if mailing direct)