First use Tools | Options and open the Calculation tab; ensure that
calculations are set to automatic

Second: no need to use SUM for every arithmetic operation: =SUM(A1-A5) is
better coded as =A1-A5
But you may have mistyped this for =SUM(A1:A5), if so please ignore my rant!

best wishes
--
Bernard V Liengme
www.stfx.ca/people/bliengme
remove caps from email

"aaron" wrote in message
...
i do a simple sum(a1-a5). it will not return a value until i do an autosum
formula.

also- when i add a number to the the blank cell in the array, the sum
formula will not automatically calculate the sum until i do the autosum
function!