When you're five years old, a year is one fifth of your life. That makes it seem like an impossibly long time, especially if you're five and have to wait until next year for something you really want. In comparison, when you're 20, a year is only one twentieth of your life, and while the days don't exactly fly by yet, a year doesn't seem like the eternity it was at five. By the time you're 50 and a year is only one fiftieth of the time you've experienced, a year whips by pretty quickly. That's the main reason that time seems to go faster as we get older. Another factor is how we spend time. Children are incredibly focused in the now. They are totally present in moment, totally absorbed in whatever they're doing. As we get older and begin to do more and have more complex thought processes, we begin to perceive time a bit differently. Unfortunately, it's hard to quanitfy these kinds of perceptions, so it's hard to say how much this really impacts our perception of time as we get older.

Its like struggling to reach the top of a pyramid.....its harder going up, than it is coming down. maybe, human life is that way. maybe, gravity has something to do with it. end

~~wrong post sorry ~~

After the age of 40, i believe anticipation sets in. anticipation that your life is likely 50% over and you truly are over the hill! You become more aware of your surroundings and give everything more attention. the days seem to blend together. closer and closer together as your age progresses. Lets face it, aging sucks. i hate it and i know most older people feel the same.

For me, personally...when I was younger I was always waiting for some point in time to arrive. When you are constantly waiting for something, it seems like it takes FOREVER. Also, I wasn't that aware of my mortality. Now that I am 25, I'm quite aware that I do have an expiration date, I want to hold on to time. It's when we want to hold on to something, that we seem to lose it much faster.

Probably because you have less of it

You have less of it to waste or enjoy.

Perhaps it deals with Einstein's time dilation, things appear to be speeding up and because when we were born it appeared slower, it appears faster later on, and children who are born at that time see time travelling slower as they don't have anything to compare it to :D I only really wanted to say that to sound smart :D

Defiantly after I got out of school time started speeding by.

Because as you get older your forget things like what you ate for dinner yesterday, what day it is, ect. lol i guess really cause you have more stuff to do but thats completely opinion.

I think because of how we perceive time. When you're a kid time seems to go slower, Summer vacations seemed longer and years went by slower because at age 5 one year was one 5th of your life and at age 10 one year was one tenth of your life. When you hit 20 a year is one 20th of your life and by the time you are 50 it's one 50th of your life. The years seem to go by quicker because it represents a smaller and smaller percentage of your life. It's just a theory of mine. I remember being ten and hearing my Grandfather talk about how fast the years go by as you get older. I understand it now. I remember last Christmas like it was 3 months ago and here we are again.

Greater responsibilities distract you from the enjoyment of the moment giving the illusion of time passing quickly. The more focused in the moment.. the slower time seems. The more unaware as if asleep or living towards the weekend.. the faster time passes. Tis all subjective.. thus all relative.

It just seems like it goes faster because you start forgetting everything ;)

I think life goes fast when you are having a good time so the older you get the years just seem to fly by.

Because, proportionately it is a smaller part of your life. Two years between the age of two and four is half your life. Two years between the ages of 48 and 50 is only 4% of your life. Well, it sounds good when you say it fast, anyway. :) For me, the years were just whizzing by and then I got an adult apprenticeship. Then time slowed right down again, in anticipation of getting qualified and the associated pay rise. So that's how you make time slow down again!

life fucks us that way.

Because you realize there is less ahead of you than behind you.

It has been said that time seems to get faster as you age simply beacuse you feel as if you know more about your surroundings and tasks. To a child the atmosphere and the decor of a room can be overwhelming much less compleating some type of task in the misdt of all this wonderment. As you get older the world seems to make sence more and more and we become less worried with exploring everything that causes us to wonder and use logic and reason to explain it as we get on with our lives that become more and more time based and task oriented and necessary to maintain a lifestyle.

My theory is that it's because school is so boring. Once you're finished school -- you just doing what you've chosen to do -- and there's not enough time to do everything you want to do.

I subscribe to the "% of time lived" theory that most people have cited here but I find it to be in conflict with my religion. It seems that most religions, including my own, believe that the soul is eternal. If this is the case then our perception of time should be constant relative to an infinate number of moments. Every measurement of time we are capable of comprehending is just a tiny fraction of eternity. Does anyone know how to resolve experience vs belief in this case?

Because it is real...The atomic clock has been adjusted in 1996 and 1998 as the frequency of Earth has been raised from original 7.5Hz to 10Hz...The frequency of Earth is still raising and we can expect that the atomic clock will be adjusted again in next year(Did you ever think about it, why you still had to adjust your wrist watches or watches on the DVD player according to real time on internet or TV?). The frequency raises exponentially, now we can enjoy 16 hours of a day in 1960 and in 2012 one day will take 1 hour of the primal day in 1960. These all are facts from researches, just think about it...

Because you end up concentrating on alot more than you did back then, like kids, will the car start, how am Igoing to pay tat bill and so on. At lest that's how it is with me.

i dont know and i dont like it =[ ...ever since i turned 18 my years has gone faster...

I'm 65 and I have a theory about this. I think it's an attempt by the mind to protect itself. Think about it ... the more memories we accumulate, the more difficult it is to keep them sorted out. The less intensely we feel things, the less the minor aches and pains of old age bother us. The more problems we incur ( fading eyesight, creaky joints, loss of balance, slowing of memory recall, hearing loss, etc, etc ), the more we will welcome death as an old friend.

I suspect the answer is somehow attached to something we've all heard about from 'near-death' experiences. "I saw my whole life flash before my eyes". So what if 'death' removes the effect of 'time', allowing us to remember every moment of our lives. Then the effect of time increases as we age, causing us to forget more and more and speeds(increases) up as we near the end. Adam & Eve were supposed to live forever, their punishment was death, this being the imposition of time as opposed to their previous state of timelessness (eternity)?

Others have already mentioned that each year represents a proportionately smaller segment of your life, so I thought I'd point out something else. Most people fall into a daily routine where nothing unusual ever happens. Our culture develops systems for smoothing our deaths, financial hardship, births, and so on, so that no one ever need be overly concerned. People's lives are planned by the State from the moment they're born to the moment they die so as to cause minimal fuss and disruption. The way the human brain (and other brains in general) work(s) is extraneous data is discarded to ensure that critical data is always able to get through. A frog's brain is so simple that it edits out anything which doesn't move erratically; large erratic objects are predators to be avoided and small erratic objects are prey to be eaten. Snakes are efficient predators of frogs because their smooth, sinuous movement makes them literally invisible to frogs. Human brains, while more complex, work much the same way. As time passes, the uninteresting daily routine gets edited out of your experience. Sadly, for most people, this means they blink at age 9 and suddenly they're 65, on their death beds. The best way to avoid having time whiz past at breakneck speed, rushing you to your death, is to make sure you never fall into routine. Take up new skills constantly. Challenge yourself always, and take on slightly more than you can handle. Throw yourself into crisis willingly, and tantalize yourself by the occasional brush with lethal danger. I'm 39 years old, never had a wife, no kids, no car, no career, no insurance, and my income hasn't exceeded $10k per year in a decade. I'm an anarchist activist, a street organizer, I've done time in jail, and fighting with riot cops is a pleasant and relaxing hobby. When at last I go to my final rest -- with any luck, still wearing my combat boots -- I'll have sucked every drop of experience from my life and be well ready to throw the husk away.

Here is my Theory on why time seems faster when you get older. You brain is slowing down like a shutter on a camera the faster the shutter speed the slower objects move when you see the film. If you take a video at a super high frame rate you can see the object move like a humming bird flapping its wings will freeze the wings in flight. So when your young your senses are working much faster this is why your reflexes are so much faster when young. You can react to things faster catching a ball or hitting a ball with a bat. Your senses sight, smell, hearing is what you know as time of day or the day of the year. If your brain slows time goes by faster like a shutter slowing down sit there and watch a clock tick when I was young it seemed like a summer vacation was as along as winter but it was really only 3 months. I never really noticed it until my late 30's. I also noticed it now that I have been at the same job for 8 years see the same people everyday.

Because we have more leisure time and fewer responsibilities as children than we do as adults. When you are busier or you have deadlines (such as bills to pay) time goes by faster.

Yep and I haven't even accomplished anything close to what I want. Time is ticking and I'm only getting older.

Yes.

While there is certainly a psychological aspect to it as many here have said, it is also a physical process. It has been shown that the levels of dopamine in the brain effect time perception. Subjects with increased levels of dopamine reported a significantly higher number than those with average levels when asked to guess how much time had passed. Similarly subjects with low dopamine levels guessed significantly lower than average. Of course, studies have yet to be done which show this to be true on large time scales(ie years) However, dopamine levels decrease as you get older. People with Parkinsons have a dopamine deficiency and sometimes have trouble perceiving time.

Because we have more to do as adults...and, "Time flies when you're having a good time!"

I think it's simply because your more occupied as an adult than you were as a kid.