1) The months pass faster than when I was younger.
2) I feel slower mentally. The ideas come at a markedly lower rate.
Is it possible that these two observations are sides of the same phenomenon? Perhaps my perception of time is based upon how fast I think. If my younger self had 1000 ideas a month, and my present self creates 500 ideas a month, then do I perceive 2 months as taking as long as 1 month used to take? It seems likely.