Using .formula to sum values in dynamic ranges - vba

Question

I created a macro that changes the layout of a raw excel file and displays some usefull information to the user. But I am stuck now.
I want to display the sum of some cells in a column, but the cell where the sum is and the column itself is set dynamically.
My layout looks like this:
Year1 Year2 Year3
Sum1 100
Sum2 50 48
Sum3 72 81
Sum4 26
------------------------------------------
Total
I want to display the sum of (sum1, sum2, sum3, sum4) in the Total row under each Year.
The thing is my years are set dynamically depending on the value of a parameter (i.e. I can have 2, 3 or 5 years).
I know I can do it using Range.WorksheetFunction.Sum but the problem is my values are subject to some changes after the macro has been used and if I use this function the values won't change afterward.
That's why I want to use the function Range.Formula to display these values as I can enter the sum like I did for the values already in the sheet.
But unlike these values (that are the sum of values in an unique column easy to select), I am not able to select the colum dynamically.
Here is what I tried to give you an idea of what I want to do if it is unclear to you:
For i=0 to Duration-1
Sheet2.Range("D" & RNumber + 7 + Duration).Offset(0,1+2*i).Formula="=SUM(Sheet2!" & Range("D" & RNumber + 6).Offset(0,1+2*i) & ":Sheet2!" & Range("D" & RNumber + 6 + Duration).Offset(0,1+2*i) & ")"
Next i
But it doesn't work as the sum doesn't recognize the range. I know I should have something like
"=SUM(Sheet2!E" & Firstrow & ":Sheet2!E" & Lastrow & ")"
but then i won't be able to select my colum dynamically.

Answer 1

It looks like your problem stems from the fact that you can't do things like "Sheet2!" & D+3+1 for columns the same way you can do "Sheet2!D" & 5+6+2 for rows. My opinion is that this is one of the many flaws created by the insane A1 reference style, and the best way to attack this problem at the root is to simply switch to R1C1 at the beginning of the macro.
With Application
If .ReferenceStyle = xlA1 Then
.ReferenceStyle = xlR1C1
End If
End With
Some day, I plan to start a non-profit effort to rid the world of the mis-begotten $A4:B$3 craziness altogether. But too many people are used to A1. And if you send your boss or co-worker a spreadsheet with numbers for columns, she might get upset or confused.
So the other solution is to introduce some ADDRESS() elements into your SUMs. The ADDRESS function takes only numbers (well, string for sheet reference) and will return a cell reference in whichever style you want.
For i=0 to Duration-1
Sheet2.Cells(RNumber+7+Duration, 5+2*i).Formula = _
"=SUM(INDIRECT(ADDRESS(" & RNumber + 6 & "," & 5+(2*i) & ",1,TRUE,""Sheet2""),1):" _
& "INDIRECT(ADDRESS(" & RNumber + 6 + Duration & "," 5+(2*i) & _
",1,TRUE,""Sheet2""),1))"
Next i
Or you can use Application.WorksheetFunction.Address() and avoid having the INDIRECT()s cluttering up your fomulas.