I have the following code:

Private Sub Worksheet_Change(ByVal Target As
Excel.Range)
With Target
If .Address(False, False) = "B1" Then
If IsNumeric(.Value) Then
Application.EnableEvents = False
Range("C1").Value = Range("C1").Value
+ .Value
Application.EnableEvents = True
End If
End If
End With
End Sub

This is a two cell accumulator that works for ONE row. I
would like to modify it to work for ALL rows in a
worksheet. Any help would be appreciated.