If anything in cell.. then put period in cell beside

Beautiful... works like a charm

Dear Jerry,

Would it be better if we use intersect so that when the data gets huge, this will only run macro on the specific cell updated.

Option Explicit

Private Sub Worksheet_Change(ByVal Target As Range)
Dim cell As Range

On Error Resume Next
If Not Intersect(Target, Range("D:D")) Is Nothing Then    

Application.EnableEvents = False
    If Activecell <> "" Then
        Activecell.Offset(, 1) = "."
    Else
        Activecell.Offset(, 1) = ""
    End If
    Application.EnableEvents = True

End If 


End Sub

Pls advice as I am also exploring.

Cheers,
CL