How to turn off auto update on a formula
 

I have a monthly time card file that we use to record the hours an employee
works on different projects for the month. For each day, there are five rows
that the employee can use for different projects. If the employee does not
work on any projects, they would put their total hours in the sixth row on
the sheet. Finally, in the seventh row on the sheet we sum the 5 rows with
project hours.

If an employee puts hours in rows 1-2 and then enters hours in row 6, the
sum in row seven does not change. However, if the employee puts hours in
three rows and then enters hours in row 6, the sum in row seven changes to
sum rows 1-6 instead of 1-5. What option do I need to turn off to make the
formula stay the sum of rows 1-5?

Thanks
Dave