How to calculate workdays and compensation for given period based on Employee's monthly salary? - excel

Question

I have only three editable fields:
salary = 15,000
start date = 18 Jul 2014
end date = 12 Oct 2014
With these fields, I need to calculate the total salary I need to pay. Payment is on a monthly basis:
(JULY = 15,000 / 31 * 14) +
(AUG = 15,000 / 31 * 31) +
(SEPT = 15,000 / 30 * 30) +
(OCT = 15,000 / 30 * 12).
I can get total days based on both dates (ie 87 days, =DAYS($enddate,$startdate)+1) ) but I need to split the days according to the months.
What formula do I need automatically to get the amount, because each person will have different salary and different dates?

Answer 1

You can use Excel VBA custom Function to solve your problem:
1). First, you should populate Excel Worksheet with data structure reflecting Employees Name, Monthly Salary, StartDate and EndDate, like in the following sample:
Employee M.Salary Start Date EndDate
John $15,000.00 7/18/2014 10/12/2014
Ann $20,000.00 7/19/2014 10/13/2014
Peter $16,000.00 7/20/2014 10/14/2014
Jeff $25,000.00 7/21/2014 10/15/2014
2). The DAYS in date range can be simply found by subtraction (EndDate-StartDate), because the underlying data type in integer
3). For general solution to the problem (Calculate the compensation for any arbitrary period and monthly salary) you will need to create custom VBA formula and use it in a separate column for each Employee. Refer to this article for explanation: Create a custom worksheet function in Excel VBA
4). Pertinent to your particular case with fixed date rage, the simplified solution based on the Excel Worksheet formulas (no VBA) is described below:
Employee MoSalary Start End Days FullMo FirstMo LastMo Total
John $15,000.00 7/18/2014 10/12/2014 87 30000.00 $6,774.19 $6,000.00 $42,774.19
Ann $20,000.00 7/18/2014 10/12/2014 87 40000.00 $9,032.26 $8,000.00 $57,032.26
Peter $16,000.00 7/18/2014 10/12/2014 87 32000.00 $7,225.81 $6,400.00 $45,625.81
Jeff $25,000.00 7/18/2014 10/12/2014 87 50000.00 $11,290.32 $10,000.00 $71,290.32
4a). In column E starting with row 2 add formula for DAYS : =(D2-C2)+1 and extend it for entire range
4b). In column F starting with row 2 add formula for whole months : =2*B2 and extend it for entire range
4c). In column G starting with row 2 add formula for the first month : =14*B2/31 and extend it for entire range
4d). In column H starting with row 2 add formula for last month : =12*B2/30 and extend it for entire range
4e). In column I starting with row 2 add formula for total compensation : =SUM(F2:H2) and extend it for entire range
Hope this will help. Best regards,

Answer 2

I have split this out because I am not entirely sure what you require and you may be able to assemble the pieces in a way that better suits you:
Assuming your data is in A1:A3, put 1/7/14 in C1, 1/8/14 in D1, 1/9/14 in E1 and 1/10/14 in F1.
To count the number of applicable days by month, in C2 enter:
=IF(MONTH($A2)=MONTH(C1),EOMONTH(C1,0)-$A2+1,IF(MONTH($A3)=MONTH(C1),DAY($A3),EOMONTH(C1,0)-EOMONTH(C1,-1)))
To compute the salary for the month by computing the daily rate for the applicable month and multiplying that by the number of days from above, in C3 enter:
=$A1*C2/(DAYS(EOMONTH(C1,0),C1)+1)
Format C2:C3 to suit and copy across to F2:F3.