Data analysts Experian contend that the old class system isn't flexible enough to be of use to supermarkets when deciding such matters as where to put their stores, what kind of music to have on the PA, or whether to move the beer next to the nappies after 6pm (as some stores do) so after-work booze-hound fathers will remember there's something in their lives other than themselves. The old A-E classes are tied to occupation, which is insufficient data for a supermarket which is trying to lure cash-rich plumbers to buy their poncy coffees, rather than molecular biologists (say) who can only afford gruel and coarse toilet paper.

To deal with this, Experian has devised a consumer classification system called Mosaic UK, which many supermarkets use to help make key decisions (where to put a store, what to fill it with, etc). Using the 2001 Census figures and data on such things as county court judgments, credit ratings, qualifications, car ownership, age and background, and working on this data with geodemographic software, Mosaic UK divides the country into 11 groups, each of which is given an evocative name and a stereotypical - and determinedly heterosexual - couple to match. These 11 master categories break down into 61 delightfully named sub-groups (Golden Empty Nesters, Dinky Developments, White Van Culture, Town Gown Transition etc).