Did you see the results of a survey of 2,000 individuals which indicated that most people don't think they are truly grown up until the age of 26. And, in case you're not quite sure, the report also listed the 50 tell-tale signs of full-blown adulthood.

We will come back to those later, but I must say the headline findings made me feel very old. I am of a generation which grew up rather more quickly: by 26, I'd been working for seven years, was on my second mortgage, my third car, and hadn't even heard of a gap year.

I vividly remember the things that made me feel like a grown-up, and they occurred long before my mid-twenties. For instance, being able to smoke in front of my parents.

They knew I smoked, of course. Having my bedroom windows open in the middle of winter was a bit of a giveaway. As were the burn marks on the sofa and carpet every time they went away. Nevertheless, when you are actually invited to smoke, and offered a light, too, it felt like a proper rite of passage.

As was calling your parents' friends by their first names, rather than Auntie this and Uncle that. And, of course, there was swearing. My parents were keen to reprimand me for the use of bad language, but once I'd heard my father let fly a volley of expletives when his car broke down, I'm afraid that was a difficult line to hold.

We live in far more liberal times today, and, as the father of a 23-year-old woman, I'd long ago given up on suggesting she might use a little less Anglo-Saxon in her everyday conversation. ("It seems only yesterday I was taking you to see The Lion King," I say to her, "and now you're calling me a ******* ******.") The familiar refrain is that kids grow up so quickly these days. They have more choice, fewer restrictions, more peer pressure, bigger academic demands, a greater exposure to commercial blandishments, and a more acute awareness of the dangers that lurk round every corner.

But, this latest research, undertaken by Skipton Building Society, suggests, despite all these factors, young people are, whether by choice or social circumstance, delaying the onset of adulthood. I also think the parents are to blame. It is particularly the case in middle class families that the children aren't even encouraged to take responsibility for their school work, with parents taking an unhealthily intense interest in their academic achievement, often shouldering the homework burden.

And if the youngsters are not taking responsibility for their algebra, how will they cope with some of the 50 benchmarks in this report, like being able to bleed a radiator, change a lightbulb or car tyre, or wearing a coat on a night out? But who am I to judge? Other indicators are an enjoyment of gardening, listening to Radio 2, going to bed before 11pm and owning a lawn mower. I may not be a grown-up after all.

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