I have used the NOW() function to automatically set in today's date when I am
entering data in Excel. The problem is the spreadsheet is an ongoing report
so when the user is done inputting data they save it and close it. The next
day a user will open it and save data and close it.

The problem is that when I use the NOW () function, the dates of the
previous days switch to the current date. I understand why that happens, but
I don't want the dates to change for the previous data. Data is not entered
every day, but almost (even on weekends).

I saw the TODAY () function, but I fear it will have the same results.

What is the formula I should use?