The FCRA sys that a baddie like a CO or CA can report up to 7 to 7.5 years from the DOFD of the debt. EQ will often list DOFD. EX and TU will usually list the drop off dates. You'll need to pull your reports from annualcreditreport.com or directly from each CRA to find the drop off dates.
Dates of last activity, dates of reporting of a collection, dates of reporting of a charge-off, dates of payment, etc., etc., are all irrelevant.
FCRA 605(a) defines the relevant dates, which in summary are, for account-related items:
For regular monthly account delinquencies, 7 years from the date of occurance of the individual delinquency. FCRA 605(a)(5); the catch-all provision, as the FCRA does not specifically mention monthly account delinquencies.
For a charge-off or a collection, 7 years plus 180 days from the DOFD on the OC account. FCRA 605(a)(4), as clarified by section 605(c).
The DOFD is defined in detail in section 623(a)(5), without ever using that specific term.
For a court judgment, 7 years from the date of entry of the judgment. FCRA 605(a)(2).