Have you inadvertantly switched calculation to Manual rather than
Automatic? Does the formula resolve itself (ie recalculate) when you
press F9? If so, you should go to ToolsOptionsCalculation tab and
check Automatic Recalculation.

Hope this helps!

Richard

ksyoung @ novanthealth wrote:
I am attempting to copy and paste a formula down a column. However when i
choose paste, the value of the copied cell appears, not the formula. For
example:
a1=2
b1=3
a2=4
b2=5

Formula typed in c1: =+sum(a1:b1), returns 5
When I copy formula and paste to cell c2 it returns "5", not 9.