How to: identify repeat offenders within a 3 week period (week per week basis)

Hi,

I'm new to this forum and I badly need help.

I work as a Quality Administrator for a customer service company and I need to identify repeat offenders within a 3 week period. I'll try to explain what I need to show as accurate as I can.

I evaluate my agents 5 times a week (1 evaluation per day) and I need to determine who repeated the same offense/markdown within a 3 week period but the catch is I need the week per week data.

Basically, if the agent committed the same mistake more than once in the same week, it does not matter but if he did it again the next week or the week after that (within a 3 week period) then he'll get a notice/memo.

So far, this is the only formula that I've come up with (got it from someone with a similar problem) but since I need to show the week-per-week data, it only complicates things for me.

=IF(D2-MAX(IF(($H$2:$H$51=H2)*($E$2:$E$51=E2)*($D$2:$D$51<D2), $D$2:$D$51, ""))<21,TRUE,FALSE)

Please advise if this is possible. I have attached a sample of the excel sheet that I'm working on so if anyone has a better idea or if anyone wants me to clarify anything, let me know.