Likely you are not rounding the numbers, just formatting them.
Formatting changes the display, but not the actual value of the number.
Use the ROUND() function in the formula to actually change the value,
or go to Tools|Options|Calculation and check Precision as Displayed.

Jerry

Danny wrote:

I have a formula that collects data, adds it and puts the information in
cells in a column. Each row in the column uses the same formula and collects
the same data but for a different hour. Most of the time the resulting numer
is rounded off by the formula. At the bottom of the column is a cell that
totals all the numbers in the column. What would cause the information in
this total cell to round down when all the numbers in the column are whole
numbers? Add the numbers with a calculator and you get a different number
that what the total cell has.