Have you got to the place where you can't remember as much as you once did?  Some say this is on account of age but that is not necessarily true.  I taught high school for 16 years and I know for a fact that that their "rememberers" weren't working all that well either.

Perhaps it has something to do with the number of tasks you have stored in your brain at any one time.  I know those high schoolers had a lot: parties, part-time job schedules, parties, chores at home, parties and of course, homework (not).