How old are you? And are you happy? The two questions actually sit quite naturally side by side, since your answer to the first is likely to have a very real bearing on your answer to the second.
In fact, research shows that the younger or older we are, the happier we are likely to be.
It shouldn't come as any surprise to learn that children are for the most part pretty happy. After all, they have lots of play time, get everything done for them and don't have to worry about paying the bills.
We also know from our own experience, that things start getting a bit more complicated when we enter our teenage years. That can be an upsetting time, with plenty of ups and downs as we discover more about the world, try to find out who we are, and start leaving the comfort of early childhood behind.
After that, we'd all like to think that things can only get better as we start to earn our own money, build a career and enjoy holidays ... without our parents.
Unfortunately, the benefits that come with maturity don't seem to add much to our happiness. In fact, research shows that we slide towards being less and less happy as we approach middle age.
That can feel like a disappointing prospect if you're only 20 right now.
Fortunately, things start to look up again after that, as we get the hang of looking more and more on the bright side of life. And from surveys of over half a million people in more than 70 countries, it seems that wherever you live in the world, you will experience what's referred to as a 'U-shape pattern of happiness'. However, the low point of life is different depending on where you live.
So, here in the UK, on average we are at our happiness 'low' when we're 35.8, while it's ten years later in America. And in Italy, it's 64.2!
What's the reason for this characteristic profile?
Well, it doesn't seem to be down to the decrease in life's pressures that's normally associated with getting older - even if you take the kids and mortgage repayments out of the equation, the U shape is still there.
Neither is it because older people today are living at a better time. And it doesn't matter whether you are single or married, well-educated or not, employed or out of work, the U shape still applies.
You even find it in our primate relatives, the great apes, such as chimpanzees, gorillas and orang-utans, according to research from the University of Warwick. And no, it wasn't the apes who did the happiness test, but their keepers, who assessed how happy each of their animals was.
If apes have the same happiness pattern as us, we can be pretty sure that socio-economic issues aren't influencing them, so there must be a more general underlying reason at work.
So what's the significance of happiness, or lack of it?
Well, happiness is often linked to long life and vice versa. So, if you're pessimistic and have a bleak outlook on the future, chances are that you won't be around as long as an optimist. That may well be because of the illness-inducing stress we bring upon ourselves by being too negative - a case of the 'survival of the happiest'.
On the other hand, one thing optimists are good at is looking on the bright side of life. And they can only do that by 'discounting' bad news - in other words ignoring it entirely or giving it less value. This means they give greater standing to good news, which makes them feel happier.
And youngsters and the elderly are much better at ignoring what they don't want to hear than the middle aged.
Of course, there are obvious downsides to this approach. It's one of the reasons smokers ignore the health warnings on cigarette packs, convincing themselves that the increasingly dire messages they see there apply to someone else, so side-stepping the well known and proven risk they are putting themselves under.
But the upside is that discounting bad news is actually good for preserving our mental health, for instance helping to protect us from the depression that can set in if we absorb too much bad news.
So what is the cure for unhappiness?
It's simple. Concentrate more on the good than the bad. This may not always result in an accurate reflection of reality, but it should mean that overall you'll be happier than you would otherwise be. After all, it is up to you whether you see a glass that is half full or one that is half empty. Your perspective on life determines everything you experience!
And you should look for ways to actively make yourself happier. In other blogs I've written about the benefits of focusing on the now.