Converting Excel Formula to VBA Code With Dynamic Reference - vba

Question

I have in my code variable named MyCol that gets the number of the column by month that was selected in a userform. for example October is in column U and November is in column V. I have a formula that I recorded and the month that was chosen is part of it but it is a problem because RC format is with specific reference and my variable is an integer.
I want that the formula will be dynamic.
This is the formula (column U means month that was chosen):
=IFNA(IF(VLOOKUP(AA2,sheet1!F:F,1,0)=AA2,U2,0),0)
That is the relavant part of the code:
Dim MonthName As String
Dim myCol As Integer
MonthName = ListMonth.Value
With MainWB.Worksheets("sheet2")
.Activate
.Range("L1:W1").Find(MonthName, , xlValues, xlWhole).Activate
End With
ActiveCell.Select
myCol = Selection.Column
Range("AB2").Select
ActiveCell.FormulaR1C1 = _
"=IFNA(IF(VLOOKUP(RC[-1],sheet1!C[-22],1,0)=RC[-1],RC[" & myCol & "],0),0)"
Range("AB2").AutoFill Destination:=Range("AB2:AB" & MLR), Type:=xlFillDefault

Answer 1

Replace your :
Range("AB2").Select
ActiveCell.FormulaR1C1 = _
"=IFNA(IF(VLOOKUP(RC[-1],sheet1!C[-22],1,0)=RC[-1],RC[" & myCol & "],0),0)"
With:
Range("AB2").FormulaR1C1 = _
"=IFNA(IF(VLOOKUP(RC[-1],sheet1!C[-22],1,0)=RC[-1],RC[-" & Range("AB2").Column - myCol & "],0),0)"
However, if you want to make your code run faster, and also avoid all the unecessary Activate, ActiveCell, Select, try the code below:
Dim FindRng As Range
MonthName = ListMonth.Value
With MainWB.Worksheets("sheet2")
Set FindRng = .Range("L1:W1").Find(MonthName, , xlValues, xlWhole)
End With
If Not FindRng Is Nothing Then
myCol = FindRng.Column
Else ' find was not successful finding the month name
MsgBox "Unable to find " & MonthName, vbCritical
Exit Sub
End If
Range("AB2").FormulaR1C1 = _
"=IFNA(IF(VLOOKUP(RC[-1],sheet1!C[-22],1,0)=RC[-1],RC[-" & Range("AB2").Column - myCol & "],0),0)"