counting duplicate values in a coloumn

I included both the formula and the value methods. For the first set, I inserted the formula. For the second set, I set the value.

Sub CountEntries()
  Dim a As Range, d As Range, g As Range, cell As Range
  Set a = Range("A2", Range("A" & Rows.Count).End(xlUp))
  Set d = Range("D2", Range("D" & Rows.Count).End(xlUp))
  Set g = Range("G2", Range("G" & Rows.Count).End(xlUp))
  For Each cell In d
    'cell.Offset(0, 1).Value2 = WorksheetFunction.CountIf(a, cell)
    cell.Offset(0, 1).Formula = "=CountIf(" & a.Address & ", " & cell.Address & ")"
  Next cell
  For Each cell In g
    cell.Offset(0, 1).Value2 = WorksheetFunction.CountIf(a, cell)
    'cell.Offset(0, 1).Formula = "=CountIf(" & a.Address & ", " & cell.Address & ")"
  Next cell
End Sub