FTE Calculation for 3 shifts?

I have a building that has 2 floors, each with 3 FT shifts, but with different personnel counts. I came up with an excel sheet, but I'm not sure if my ending calculation of the FTE for the building as a whole is the correct way? Or if I need to show FTE per floor separately. Here's what I came up with. Shift 1 - 6:30am-3:00pm shop (1st floor) ---310 x 8.5 (hrs/day) = 2635 (total hrs/day) engineering (2nd floor) ---100 x 8.5 (hrs/day) = 850 (total hrs/day) Shift 2 - 2:30pm-11:00pm shop (1st floor) ---310 x 8.5 (hrs/day) = 2635 (total hrs/day) engineering (2nd floor) ---60 x 8.5 (hrs/day) = 510 (total hrs/day) Shift 3 - 10:30pm-7:00am shop (1st floor) --50 x 8.5 (hrs/day) = 425 (total hrs/day) engineering (2nd floor) ---30 x 8.5 (hrs/day) = 255 (total hrs/day) FTE (M-F) 5 day work week shift 1 --- 3485 (hrs/day) x 260 (# work days/yr) = 906,100 (total hrs) shift 2 ---3145 (hrs/day) x 260 (# work days/yr) = 817,700 (total hrs) shift 3 ---680 (hrs/day) x 260 (# work days/yr) = 176,800 (total hrs) TOTAL HRS worked/yr----------------------------------= 1,900,600 (total hrs) 1,900,600 / 2080 (hrs of work days/year) = 913.75 = 914 (FTE) Can someone help and tell me if I did this correct?