The same principle applies to the funding of higher education. Pump in more cash and you can teach more students and, if you get it right, improve the quality of teaching and research. It does not require a degree from Harvard to see that the richest academic institutions in the world are usually the best.

But now students are being told (as they long have been in America) that the more cash they invest in their education, the better it will be. Our system is creaking, the Government says, and the only way that the leading institutions will compete with the Harvards of this world is to charge top-up fees.

The favourite statistic of Margaret Hodge, the Minister for Higher Education, is that the average graduate can expect to earn about £400,000 more in a lifetime than a non-graduate. The problem is that once you start claiming that the more money students put in the more they will get out, the more difficult and demanding they will become. There was a time, not long ago, when the idea of weighing up how much more money one could expect to reap from studying at a particular university, or taking a specific subject, would have crossed the minds of few prospective undergraduates. Most people accepted that there was a handful of elite universities, and competition to get into them was always tough. And some thrusting types were convinced of the future fiscal benefits of a degree in business studies or management at a particular institution. But most of us simply wanted a good education, a good time and a halfdecent job at the end of it.

However, if universities are going to be able to demand various levels of tuition fees, it is only natural that A-level students (and their parents) will start asking more probing questions about what they will get in return. One of those questions, inevitably, will be: what sort of salary will I enjoy if I come and study with you?

Jeremy Smith, of Warwick University — an expert on rates of return on education — believes that as universities fight harder to get the best students, those students will become increasingly picky. “They will be able to phone admissions tutors and say: ‘I have got this offer from this university, I’ve got three As, why should I come to you? What is your degree going to pay me in the labour market?’ ” A report last year by the Organisation for Economic Co-operation and Development said that investing in a degree gave a better return than putting your cash in government bonds, and that British graduates could expect a 17 per cent return.

But academics, such as Libby Aston, of the Higher Education Funding Council for England, suggest that even such studies are misleading. They point out that there is no proper control sample of young people who were of university ability and who had the relevant A-level grades but did not go to university.

More specific data that would allow comparisons of the salaries of graduates from different universities is even harder to find.

The Association of Graduate Recruiters conducts a survey, but only of those who are employed by its blue-chip member companies. The Higher Education Statistics Agency conducts a first destination survey, which is sent out to new graduates six months after they leave higher education and has a response rate of more than 70 per cent. To date, it has not asked about salaries, but, because of the growing demand for data, it will begin doing so from 2004.

Smith says that gathering data after six months is too early to be very useful; many students are still looking for jobs, taking time out or undertaking further training. He says that the categories of job used in the survey are also too broad to offer students a clear idea of what they might be earning in specific fields.

It is likely that universities will try to conduct their own surveys of their alumni and use them to woo students, he says. The risk, in a competitive market, is that universities will be selective in what they reveal, and even in who they question. “If you know that your data is going to determine the number of students you get, are you going to make more effort to track down Billy, who never went to lectures and got a third, or Jane, who got a first?” Smith asks.

“I think that if the Government is going to go down this route with tuition fees there can be only one outcome: that more information has to be provided. If you are paying for a service, you want to know what you are getting.”

The central problem is that “in the short term, that information is not going to be there. It’s going to be a mess”.

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