Need ideas to get column exact totals.

[kachaloo]

Hello guys.
I have made a sheet preparing payslips for emloyee however I am adding a rule to see if the employees is a Director then the calculations in each columns are done on cumulative basis.
i.e. every employee has monthly LEL(1a) = 6032/12=503, LEL-PT(1b) = 2392/12=199 and PP-UEL(1c)= 8424/12=703
for example a normal employee with 1720 salary a month The boxes 1a=503,1b=199,1c=1702-503-199=1018 and the employee pays national insurance on 1018
for Director a cumulative approach is use. i.e. no insurance is charged till 6032+2392=8424 is reached as see n in the first photo.
In here the director is paid 1720 every month. so the first column-1a only calculates till 6032 then the second column 1b calculates till 2392 and the third column-1c would activate when the total is more than 8424

I need help with formulas to assess the total of the column/todate before do any calculations.

I hope it make any sense to you. I have thinking for two days now but I lose my train of thoughts after a while

 

[Yongle]

The easiest way to do this is to
- insert a column (X) for "Pay for Month" (actual £amount is entered)
- insert a column for "Cumulative Pay" (Y) with formula in Y2 copied down =SUM(X$2:X2)
- create named range LEL with RefersTo =6032
- create named range PT with RefersTo =2392
- above can now be used in formulas in other columns

£6032 is an annual limit - are there any monthly limits?
same question for £,2392?