Forecasting Formula

[Cwynot]

Hello,

I've got a situation where I want to forecast out how many hours it takes to build something by department. However, the hours all are in different periods of time depending on department. I need the hours to calculate correctly based on the month it's shipping. Below is what I want. Attached is the input data. 

Model TDX-1500 

Shipping Qty 2 in October

Baytown October Hours = Qty 2 * 2.50 hours per month

Baytown September Hours = Qty 2 * 0 hours per month

Thanks,

Courtney