it has more to do with body temperature than it does with anything else...time goes "faster" in the morning because your body temperature is different than in the afternoon for example...the same holds true for when you age, your perception of time speeds up and times goes by "faster"....
it will never be meassured exactly because the chemical clock theory is impossible to test...time has never been more relative
interesting fact: a 100 year old women has perceived less time than a 100 year old man due to the difference in body temperature or chemical clock...even though they botch clocked in 100 years the woman has perceived 20-30% less
another argument is IQ...
everybody has intellect, even a slug, intellect is defined as the ability to solve problems....
intelligence is the speed of the ability to solve problems to put it simple...
if you can process more data in a shorter period of time then it is fair to claim that you perceive more than somebody who can not...