Macro To Add Conditional Formatting To Variable Range

I have 2 columns 'C' and 'D' which I want to apply Conditional Formatting to (i.e. colour the background of the cell in column 'D' for the respective row in colum 'C') if they contain different values. I have the following

Sub CellCCondFormatting()
Dim j As Long
Range("C2").Select
j = Range("C2"). CurrentRegion.Rows.Count
MsgBox ("1st: " & j)
Range("C2:C" & j).FormatConditions.Delete
Range("C2:C" & j).FormatConditions.Add Type:=xlCellValue, Operator:=xlGreater, _
Formula1:="=D" & j
Range("C2:C" & j).FormatConditions(1).Interior.ColorIndex = 3
Range("C2:C" & j).FormatConditions.Add Type:=xlCellValue, Operator:=xlLess, _
Formula1:="=D" & j
Range("C2:C" & j).FormatConditions(2).Interior.ColorIndex = 4
MsgBox ("2nd pass: " & j)
End Sub

It iterates through all rows in my CurrentRegion OK but the Conditional Formatting 'formula' operates on the wrong value in column 'D'. For example, when viewed via menu option Format > Conditional Formatting... row 2 column 'D's Conditional Formatting value is D1714, row 3 column 'D's value is 'D1715' and so on....................