"And why do people keep a calendar from 1982? It was a trophy."
Can't speak for why Kavanaugh kept his calendar but some people with an element of OCD do behave as such.
My daughter began using a day timer in preschool and still has them all. Since becoming computer facile, running trail ultras and climbing her whole live is on an excel spreadsheat. Ever mile run, every calorie consumed, ever climb completed or attempted etc. Wish I had her discipline as she studies it intensely to evaluate progress over the years.
Still remember when i did the Wapta traverse with an ultrarunner friend and he was religiously writing down times, distances, elevations each evening in his training log.
This in no way supports Kavanaugh or the entire embarrassment this whole process has been, but just wanted to point out the calendar thing is not that rare in some personalities.