This is a distinction of no real practical use, though. If you're a consultant who doesn't bother to open his own practice and does all his work as an employee of the NHS, you can make 100,000 a year, which means you're richer than many capitalists. Yet you would be in the same class as a minumum wage earner stacking shelves at Tesco. I don't see the use of such a classification.
As the label implies, it's a job-based classification, not an income classification.
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