Hi Flying_Dutcman
Only with VBA code ( change event )
Copy this event in the sheet module in a test workbook
Private Sub Worksheet_Change(ByVal Target As Range)
If Target.Column = 2 Or Target.Column = 3 Then
Cells(Target.Row, 1).Value = Cells(Target.Row, 1).Value + Target.Value
End If
End Sub
--
Regards Ron de Bruin
http://www.rondebruin.nl
"Flying_Dutcman" wrote in message
...
I need to have a collum A1 equaling the sum of collum B1 and C1. When I have
the answer in A1 and I type new value in B1 or C1, A1 must increase its value
by the number added. eg, B1 20 C1 30 A1 50. Now I change B1 to 30 and A1
gives me 80. Can this be done?