The fact that 'millennials' make up a fast declining proportion of the car-buying public has been bothering car makers for years, more so in recent years because all sales have been in the doldrums.

Marketing types have been wondering whether the recovery – when it came – would involve these people, and whether there was anything they could do to rekindle their interest.

The problem is real enough. Figures I’ve seen suggest that the proportion of under 25s buying new cars has fallen a third in 15 years, and that 20 per cent fewer 18-year-olds currently hold driver’s licences than they did in the 1960s and ’70s, when my friends and I aimed to sit our licence test on our 17th birthday.

In 2009, Ford vigorously targeted young US buyers with the new Ford Fiesta – and did okay for 18 months – until sales fell by a third in 2012 compared with 2011.

The Japanese have been so alarmed by the retreat of young buyers that they’ve been producing concept cars whose décor and dash graphics mirror those of smartphones and computer games (whose popularity is not in doubt). “Today’s young people don’t want a car,” says one expert, “they want an experience.”

My own view of the truth – garnered mostly from an absorbing recent chat with a trio of London-based 'Generation Y' types – is it that the decline of young people’s car ownership is the outcome of a bewilderingly complicated set of circumstances, the first and simplest of which is that cars, like mortgages, are damned expensive.

Other factors are that today’s overprotective parents are prepared to do the driving, that today’s licence test is enough of a hurdle to deter many, that insurance, fuel and parking are cripplingly costly and that it’s cool to cycle.

However, my trio had two points of reassurance for the motor industry. One was a certainty that a move into car ownership was coming: all saw houses and families as the future and reckoned owning a car or two would help.

Better still, all believed the progress made by car makers in reducing pollution was now palpable. Fifteen years ago, during their early education, it was not. Cars were bigger polluters per tailpipe, and there was a regrettable tendency for users to criticise and fight the effects of emissions legislation.