Get this: Happiness among human beings peaks at age 23, tanks at 55, then peaks again at 69.
So says a study by the Center for Economic Performance at the London School of Economics, as reported by the U.K.'s Daily Mail newspaper.
The findings make sense to me.
At 23, you are brimming with life. You are confident your future includes great riches and fame, a lovely wife, and a perfect family and home.
As you move along, though, it doesn't take long for the disappointments to begin piling up. The study concludes that most 23-year-olds overestimate their future life satisfaction by about 10 percent - or considerably more than that.
Pretty soon, your life is filled with meanie bosses who are under pressure to turn a profit - that's if you are able to find a job in our stammering economy weighted down by government rules, penalties and costs.
Still, when you're young, you think you have lots of time to figure it out. But, as it turns out, you have way less time than you think.
One day, you're just out of college, trying to extend your active college social life. Pretty soon, your focus shifts to making something of yourself. You are either at work or school all the time.
Before you know it, you are 30. The college kids you were once among now view you as an old-timer. You don't feel old, though. You're still living in Mom and Dad's basement!
And while you try to find your way through your 30s - marriage and children and lots more debt - suddenly, you are 40. How did that happen?
For a few years, you remain calm. You are still somewhat young - still have your dreams to chase.
But as life - which involves speeding tickets, colds, high tax bills, unexpected household expenses and a dizzying mix of highs and lows - takes over, you realize you have little spare time.
And then, you are 50. Good God, a half-century? A half-century is supposed to be a long time - but it didn't take so long at all.
Your expectations for the future are not what they once were. You spend less time looking forward and more time looking back.
Your mistakes and regrets come into sharp focus. If only you had done this or that. If you are lucky enough to still have your parents, as I am, you are sad to see what age is doing to them.
You long for your childhood when they were young and strong - when times were simpler, and they surely were if you were lucky enough to grow up in the '70s. (I had a grand time writing and publishing a book about my experience, "Misadventures of a 1970s Childhood.")
You worry about the future more than you ever have. You are wiser and pay attention to the news. You are saddened, even angered, by our country's inability to address its core problems - spending, debt, deficit, money-printing.
You worry about the future that your children and grandchildren will know. Will they live in a country with fewer freedoms, lots more government rules and a perpetually stagnant economy, as is the case in Western Europe?
So it makes sense that one's happiness would tank at 55.
We celebrated my father's 80th birthday on Sunday. He told me that when he hit 50, time took off like a rocket. That makes me cranky, too.
It's going by too fast. I'm not accomplishing enough. My country is not accomplishing enough.
If I can hang on until I'm 69, will my happiness peak again?
I hope so. I hope our country comes to its senses and is able to unleash the ingenuity and prosperity we need to pay for all the promises we have made.
But at 51, I have my doubts, which is troubling - I still have four years to reach my peak crankiness.