If you have hire dates for 1,000 employees and need to calculate the date they convert to permanent staff three months after hire, how should you calculate it?
Method 1: +90 days?
Method 2: Month + 3?
❌ Because months have different numbers of days, adding 90 days can shift the conversion date by a few days.
For example, if the hire date is 2/20/2019, three months later should be 5/20/2019, but adding 90 days yields 5/21/2019.
❌ If the hire date falls in October, November, or December, adding 3 will exceed 12 and cause an error.
Use the EDATE function
=EDATE(hire_date,3)EDATE solves both problems; 3 means three months ahead, so to find three months earlier use =EDATE(date,-3). Microsoft's official documentation
