hi,

Let me try and explain what I am trying to do.

Period 1 Period 2 Period 3 Period 4 Period 5 Period 6 Period 7 Period 8 Period 9 Period 10 Period 11 Period 12 Total
ABC 100 586 750 288 446 474 500 296 666 345 836 718 6005
Cumulative Sum 100 686 1436 1724 2170 2644 3144 3440 4106 4451 5287 6005



Target Number 4000
Which Period? X

X = is the column in which the sum from Period 1 to Period 12 will fall in.
So in the above example, X = Period 6

Is there a formula to get this done in a better way?