Try
=IF(A1,A2+(A3*A1),"")

--
Jacob (MVP - Excel)


"jamesvh" wrote:

Hello All,

I'm having a hard time creating a formula to collect data for work. Here is
what I'm looking to do:

To explain I will use cells A1, A2, A3 & A4. To start cells A1 & A4 are
empty and cells A2 & A3 have values. Now when a value is added to cell A1 sum
cells A2 & A3 to cell A4. When the value in cell A1 increses add cell A3 to
the amount currently in cell A4 and so on (see below).

A1 A2 A3 A4
7200 600

A1 A2 A3 A4
1 7200 600 7800

A1 A2 A3 A4
2 7200 600 8400

A1 A2 A3 A4
3 7200 600 9000

I have been racking my head trying to figure this one out, so any and all
help is more then welcome and thanks in advance.


jamesvh