Time really is an interesting thing. The concept of time is still weird to me. What depends on how fast or how slow you want time to go depends on what you set your mind to. For me this month, wow where did the time go? My mind is on something very important in my life right now and when your mind is occupied with things, time goes by in a flash!
But for the people that don't really have a sense of direction or no purpose in life and are always looking for something to do with themselves, that is where the time and life seems at its longest.
It really all depends what you decide to do with the life that Our Father In Heaven has given us.