There was once an age when class came with breeding. One’s parents gave one one’s position. One might stray a little above or below (a perfect marital match is never possible), but one knew one’s place, argues Danny Dorling in the latest Fabian Review.

Then for much of the last century class was about occupation – you only had to ask someone his or her job and you felt you knew almost everything you needed to know about them. But in 2008 that is no longer true. The 50 per cent of the British people who can just about pay the bills, but who should not even imagine paying inheritance tax, have a huge range of occupations. Just as those above and below them do. These middle class families tend to have two jobs (the British norm), two cars (the norm), a small semi-detached or large terraced house, a combined income that pays the mortgage, food, fuel and a couple of holidays a year, (one of them somewhere warm). Nowadays, class is all about money.

In the 19th century, accent, clothing, title and behaviour reflected our origins. There were schools for all classes: the Great Schools for those destined for greatness, and a multitude of not-so-great schools – mostly created or expanded under Victoria’s reign – catering for the children of different strata of the new middle classes. You could tell whether a family was upper-middle, middle-middle, or lower-middle class from the school their children attended.

The working classes had their day schools, Sunday schools, church schools and elementary schools. You could also tell their class from the street they inhabited. Charles Booth had maps of London beautifully coloured – you could see the subtle differentiation between all the areas not shaded golden yellow, the colour of the servant-keeping classes. You could also see those areas shaded black and labelled ‘vicious, semi-criminal, poor’.

Mrs Beeton wrote a book on household management that sold well in those days. It turns out she only had one servant, but she did a good job of pretending to have more. Her book sold well because of a popular demand for information on how to act up to the class you wished to be. Just like Nigella Lawson today, she provided the fantasy that you too could appear to come from a stable above, be of better stock and be more respectable.

We used to have popular guides to the British class system that told you how to appear just a slight cut above. But in 2008 those at the top have to try to appear like the rest, chummy and normal. This year women had to be told they must wear knickers to enter the Royal Enclosure at Royal Ascot. How did we get here from there?

It was a slow change through the 20^th century. The decimation of the sons of the Great Schools in the 1914-1918 war, the ‘gifting’ of stately homes to what is now the National Trust, the collapse of the financial might of the upper class through the 1920s and 1930s, and a progressive tax regime that lasted from the end of the Second World War until the beginning of Thatcherism – all these things changed what class meant. Whereas under Victoria secondary schools had been designed to segregate the middle class, the 1944 Education Act split up the working class. It had the side effect of creating a one-off generation selected at 11 by what was called an ability test, a few of whom later got good jobs in universities and mused about class. They were almost all boys as the 11-plus tests had been made easier for boys.

Unsurprisingly, these Grammar School boys, with occupations their fathers had often not heard of, came to think of occupation and job title as very important. They designed class systems based on men’s occupations. Occupation was seen as a proxy for behaviour, for leisure pursuits, for taste, for class. Under this system the university lecturer from humble origins was equal to the don who did not need to draw his salary. Women fitted awkwardly into such schema.

Unfortunately, classification based on occupation came to predict some behaviour less well over time. Almost from the moment when the occupations were grouped, people started voting less and less reliably by occupational class. They took longer to stop behaving so predictably in lifestyle, partly because health outcomes have long antecedents, but premature mortality too has become recently a little less predictable by class.

Have we become a more classless society? It doesn’t feel quite like that to me. What I think has shifted is how we know what class we are in.

Give someone a fancy job title today and it may not mean quite as much as it did a few decades ago. You know what ‘general manager for the horizontal arrangement of goods for sale’ means, and what is being stacked where. Similarly two jobs can have the same title but be very different things. Different Members of Parliament, for instance, have very different lifestyles and differing levels of income and wealth.

Now there are better ways to gauge class. Tell me where you went to school, what your father’s job was then, and your home postcode now and I’ll quite happily put you in a pigeon hole. It still helps to know your job title, but I’m not that bothered about it. I’d be much more interested in your financial situation and that of your wider family. How many millions do you and your siblings, cousins, parents, grandparents and offspring collectively have recourse to if it were pooled? I know you’d never pool it. But it is access to just a little bit of that pool which often makes the difference between what happens to families when folk get divorced, lose a job, become sick, need a deposit or some other underwriting.

Your class is your family wealth. For many people that wealth is zero or less. If you cannot save £10 a month and take an annual holiday you are most probably poor. If you cannot do those things, and know you are poor, and you have a low income, then you are approaching another class below. Not an underclass – there really is no such thing as a group destined for the bottom due to some fallibilities they have. The very poor are, instead, those whose dream is that their greatest worry is that they cannot save £10 a month or take a holiday once a year. Roughly a quarter of people are poor, including about a tenth of the population who are very poor.

Above the poor in Britain are a group who have been squeezed in number in recent years: those who are neither wealthy nor poor. These are people who are socially included. They can partake in the norms of society. They are normal. If you are normal you can pay for the schools trips, and a holiday, but not for the holiday in Mauritius. You are getting by, but not comfortably. You are in a shrinking middle group, and any time right about now you will be in a minority. Today you make up 50 per cent of UK households. Across Britain – outside of London – most people are still normal but that normality ranges itself from living a whisker above poverty to a whisker below the wealthy.

The wealthy are the 25 per cent of the population who do have some (little) cause to worry about paying inheritance tax. Only a third of this group ends up paying it, but they almost all worry about it. You are in this group if your estate were to be liable for that tax should you and your spouse simultaneously drop dead today. Don’t forget to count those life insurance policies, or the writing off of the mortgage, or that death-in-service lump sum. But don’t worry: most people like you will manage to spend your wealth in old age long before you have a chance to pass much of it on. The odds are that you are also partaking in most of the norms of society. Most people in this group choose not to use private health and education provision. If they did, other luxuries would have to be forgone.

However, within the wealthy are a group who routinely do exclude themselves from the norms of society: for ease of remembering we’ll call them the exclusive rich. They make up just around 5 per cent of us.

What sets the exclusive rich apart from the rest is not their use of private provision, but their large properties, multiple foreign holidays coupled with the outright purchase of new cars. You need to be doing about two out of three of those things, while preferably also having a six-figure household income to be up with these Joneses.

There is a national fixation with this group, and enough written on them to sell a month of Sunday newspapers. So all I’ll say here is that they are fractal in nature. Within the best-off 5 per cent half are so much better off then the rest that they make the other half feel poor. Within that better off half, half are so much better off that... it’s a recursive definition. It ends with the poor sods at the top paranoid about being kidnapped and knowing that their children and lovers lie to them for their wealth and suspecting their servants of pilfering. This is our wealth-based British class system today.

It is a 25-50-25 division, the edges of which can be shaved off to almost infinite layers of abstraction. It may sound crude, but money is. Airs and graces no longer matter. In fact it’s crucial to try to avoid them regardless of which end of the scale you are from. Dress down if you might otherwise look like a ‘toff’, take off that tie, unclip that accent. Dress up if you come from more dour stock: sensible suits, a neat hair cut, hold your knife and fork right. All the old markers of class fade as, for men, a ubiquitous ‘bloke’ is created, and women have to lookWe can all still see the signs though. Those brown leather shoes that only men from certain (great) schools still wear, that fake handbag that only women not quite au fait would carry… but the signs matter less and less. Those whose occupations are labelled ‘working class’ still have a predilection to vote Labour more than their generally lower incomes would suggest. This means, in effect, we will not be asking about class. An income question is asked in the United States census, it is asked in censuses and surveys across Europe, it may even be asked in the 2011 census in Scotland, but it is not set to be asked in 2011 in England and Wales. There must be a civil servant living in a 1950s fantasy land somewhere who thinks that it is of some great use to know that a person’s job label is ‘Manager’. We’re only getting useful information when we know that they are a manager and that the income of their household is roughly £40k, and that only one adult in their family works Income is not being asked about in the 2011 census not because of any real fears of asking the question or because some folk might complain. It is not being asked about because we are afraid of what we will be told and of what kind of a segregated country we will see. Sometime soon, the proposed 2011 census questionnaires will be laid before Parliament. Parliament decides whether to accept what the civil servants propose. Parliament altered the 2001 form –Parliament could alter it again. Don’t you want to know what Charles Booth’s maps would look like if re-drawn today?

Danny Dorling works with the Social and Spatial Inequalities Group (SASI) in the Department of Geography, University of Sheffield. See www.shef.ac.uk/sasi. With Bethan Thomas he is author of ‘Identity in Britain: A cradle-to-grave atlas’ published by Policy Press in 2007. He is also an author, with colleagues, of the ‘Real World Atlas’ and ‘The Grim Reaper’s Roadmap’. Both are to be published in autumn 2008.