Hi Bill, are you referring to Autofill? Once you have a relative cell
reference in (without $ signs) as in your example, you move your mouse to the
lower right hand corner of that cell and your cursor turns from white cross
hair to a black crosshair, left-click and hold, drag it down as far as you
need it to go.

HTH,
Kevin M

"Bill" wrote:

forgive me if this is basic stuff but I am trying to figure out the
following: have 2 columns of numbers say C and D where I need a running
total starting at say D4 with the formula=SUM(C4-C3) then D5 would be
SUM(C5-C4); then D6 SUM(C6-C5) and so on. Is there a way to automate
this? Thanks - Bill