Hi, I'm after a bit of help please!!!

I'm trying to produce some warehouse kpi's but I am having trouble with a couple of formulas.

It's all based around the number of minutes it takes to handle product.
A total of 16 mins per piece is split between 9 mins for goods in handling and 7 mins for pick / despatch.

Goods In (6am to 2pm shift)
The first column is 'Units Expected' = 366. The second column is 'Manpower Required' which has the formula =IF(B3>0,SUM(((B3*9)/60)/7.5)," ") (B3 is 'Units Expected') which gives me 7. The third column is '6am to 2 pm Actual Manpower', which in this case = 16. The fourth and final column for the goods in process is simply called '+/-' which has the formula =IF(B3>0,SUM(D3-C3)," ") (B3 is 'Units Expected, D3 is '6am to 2 pm Actual Manpower' and C3 'Manpower Required') which gives me 9.

Pick / Despatch - Is similar to the above (2pm to 10pm shift + 10pm to 6am Shift)
'Units Expected' = 641
'Manpower Required' =IF(F3>0,SUM(((F3*7)/60)/7.5)," ") (F3 is 'Units Expected') which gives me 10
'2pm to 10pm Actual Manpower' = 16
'10pm to 6am Actual Manpower' = 8
'+/-' =IF(F3>0,SUM((H3+I3)-G3)," ") (F3 is 'Units Expected', H3 is '2pm to 10pm Actual Manpower', I3 is '10pm to 6am Actual Manpower' and G3 is 'Manpower Required') which gives me 14

The final 5 columns are meant to give me my actuals but I'm positive that 1 or more of the formulas are wrong!!!

'Total Manpower Required' =SUM(The 'Manpower Required' figure from Goods In + the 'Manpower Required' from Pick / Despatch) which gives me 17

'Total Actual Manpower' =SUM(The '6am to 2 pm Actual Manpower' from Goods In + the '2pm to 10pm Actual Manpower' and the '10pm to 6am Actual Manpower' figures from Pick / Despatch) which gives me 16+16+8 = 40

'+/-' =SUM('Total Actual Manpower' - 'Total Manpower Required') which gives me 40-17 = 23

'Total Units' is the easy one - 366+641 = 1007

The last column is the biggy and the one I think I may have proble with

'Actual Minutes per unit' =IF(N3>0,SUM(((((L3/N3)*16)/60)/7.5)*100)," ")
N3 is 'Total Units'
L3 is 'Total Actual Manpower'

My grand units minute per total comes out at 0.14. I'm almost positive that that is still too low a figure!!!

Any and all help would be most apreciated!!!

Regards,

Patrick.