Countif Formula taking into account start dates

Hello All, I have been trying to rack my brains with a formula that would help me adjust my stats according to a start date.

currently, I am using a countif formula to compile all my employees test scores

as below

=(COUNTIFS('Name List'!M:M,"PASS",'Name List'!$C:$C,Graphs!$D$2)+COUNTIFS('Name List'!M:M,"FAIL",'Name List'!$C:$C,Graphs!$D$2))/COUNTIF('Name List'!$C:$C,Graphs!$D$2)


Now, on the "Name List Tab" under column B i have added start dates of all 200+ members of staff, the problem is that the stats that the above formula takes into account everyone, including people that have started today, and they do not take the tests for 2 weeks.

I would like the stats to take into consideration the test scores after 14days so that it doesnt skew the results.

If someone could help it would be much appreciated.

Thank You

Jay