If you're happy and you know it, clap your hands.

If you just clapped, chances are you aren't middle-aged. A pair of researchers have just released a paper theorizing that a person's level of happiness over their lifetime follows a U-shaped curve with the happiest periods occurring near the beginning and end of life.

In fact, their research shows that in the United States, women are unhappiest at around age 40, while men don't bottom out until about 50. In the United Kingdom, men and women both seem to be at the greatest risk for depression at about age 44. Despite slight differences such as these, the U-shaped curve of unhappiness was found in 72 countries, meaning middle-aged misery is a global phenomenon.

Andrew Oswald is an economics professor at the University of Warwick in the U.K., and David Blanchflower is a economics professor at Dartmouth.

Together, they have become experts on the study of happiness, although I'm not sure what these economists' qualifications are if it's true that money doesn't buy happiness.

Actually, in a study they conducted in 1999, the two addressed that particular point and declared, "Money does buy happiness — but less than is generally thought." Their statistical calculations in this study showed that a long-lasting marriage brought as much happiness as an additional $100,000 in annual income. I can only conclude that if you have $100,000 and a long marriage, you must be positively ecstatic.

The underlying question I have is, how are they defining happiness? In 2007, they published, "Money, Sex and Happiness: An Empirical Study," in which they defined happiness as: r = h(u(y, s, z, t)) + e.

That's what I get for trying to read scholarly papers. Somehow that formula related to a "well-being function." All I know is it made my head hurt and encouraged me to look for the "sex" part of the study. None of which actually helps to define happiness.

Thucydides said the secret of happiness was freedom. Goethe said, "The greatest happiness for the thinking man is to have fathomed the fathomable, and to quietly revere the unfathomable." And, Charles Schulz said, "Happiness is a warm puppy."

Truthfully, I think the puppy probably comes closest to describing happiness for most of us.

Regardless of whether or not you're middle-aged, your happiness is the sum of a preponderance of smaller things combining to create a patchwork quilt of "well-being." This can range from your overall health to a beautiful sunset and, yes, a long-lasting marriage or a $100,000 raise.

A story on happiness I found on Oprah.com featured psychologist Dr. Robert Holden, founder of the Happiness Project in England. He said many people who are looking for happiness don't realize they already have it. I agree.

For me, happiness sometimes arrives in the guise of a Dodgers' broadcast on a beautiful Saturday afternoon, a new magazine in the bathroom or a nice dinner with my wife at the harbor. Other times, it's a little more complex, like seeing my children succeed or celebrating another anniversary in our long-lasting marriage (the $100,000 raise seems unlikely).

In any event, I'm not willing to cede this part of my life to a malaise of middle-aged misery.

I'm sure happiness means something different to each of us, and that means it's up to each of us to seek out what makes us happy and to embrace it. Do that and you'll find happiness.

You'll also mess up Oswald and Blanchflower's next study.

— Contact Star columnist Bill Nash at bnash805@aol.com.