Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
If Not Application.Intersect(Target, Range("I4:T33")) Is Nothing Then
With Target
If .Count > 1 Then Exit Sub
If .Value = "" Then
.Value = Cells(Target.Row, "H")
Else
.Value = ""
End If
.Offset(0, -1).Select
End With
End If
End Sub