Subjectively a good way is to remember how long summers felt when you were a kid. A summer felt like forever in the first couple of grades. Now think how long summers feel now, they just sort of fly by. It is kind of scary.

Remember my grandma sometimes got confused what day or week it was and as a kid I could never understand that. How can you miss such a long period of time like a week and not notice, but now I start to sort of understand.