Eli5: Why, if at all, does it seem like the years go quicker as you get older?

Question

I hear a lot of people making that remark, that the years go by quicker as you get older.
For me, at least, it seems like that’s only the case if nothing much changes in my life in that year.
To me, years seem to feel like they go slower if there’s lots of new/different things happening.

In: 348

Answer 1

Your personal concept of time is permanently expanding.
When you’re age 10, one year was 1/10th of your life. Time seemed to take longer because of that.

I’m now age 30, so one year is 1/30th of my life, so in comparison to age 10 the weeks/months/years seem to get faster and faster