How to Count Terminated Employees and Re-Hires for the Mandate?

How are terminated employees calculated in month FTE calculations? If I fire an employee or they quit during but are on my payroll for the first two weeks of the month and I hire a replacement for them and they are on payroll for the last 2 weeks of the month, do I have to count that as 2 full time employees or one? Or since they both only worked under 120 hours for that month do I just add the hours together and divide by 120 and count them as an FTE part time employee vs a full time employee?