Maybe happiness is meant to be the exception rather the rule.  If you're happy too much of the time, you might get too comfortable - too complacent - with the way things are and not want to change anything.  For example, if people had been happy having to light their homes with candles, we wouldn't have needed Thomas Edison to come along and invent the electric light bulb.  If in the Old West, people had been happy with the Pony Express as the major communication link between east and west, we wouldn't have needed the telegraph, telephone, and eventual global telecommunication networks.  If Americans had been happy using horses to plow their fields nad take them into town, Henry Ford would never have brought us tractors and automobiles.

    This could explain why people tend to be happier as they grow older.  Maybe it makes sense that young people are more frustrated, angrier, and more restless about life - these feelings provide the energy necessary to make things happen in terms of productivity, entrepreneurship, and invention.

    What I'm suggesting is that perhaps happiness is wasted on young and is emotion better suited to people in the other parts of life.  Why else would 38% of people between the ages of 68 and 77 report being "very happy" as compared to only 28% of those between 18 & 27?

    Look on the bright side: If you're under age 40, you have something to look forward to - a happier time of life.  If you're over 40, good news: You're already well on your way to compounding a life of happiness!