Q: Where is data for Reminders stored?

Does anyone know where the data for Reminders is stored? I need to retrieve a list from an old Time Machine backup that the system no longer recognizes as a Time Machine backup for reasons I can't imagine. I'm assuming there's no way to repair that. 

I've scoured the Library and can't find anything that seems relevant. I'm running X. 9. 5. on a 2013 MacBook Air and the data I need to recover is from 2 years ago.