Math.abs driving me crazy

Here is an example:
image
Osc[0] is a positive number and prints correctly. Osc[1] is actually a negative number, so it is printing correctly as Math.Abs() has correctly made it a positive number.
Osc_Sum = SUM(seriesOsc, 2) should be adding Osc[1] and Osc[0] and coming up with a positive number, .0188327. It is not. First of all if the series is storing positive numbers, how is the sum a negative number, and not a correct number at that.

Thanks for your reply!