The most egregious bit A bit comes from the Times: "The middle classes, whom Labour is desperate to court, were hardest hit between 2002/3 and 2003/4 by the tax changes. A single-earner couple on £40,000 with one child would have lost £117 per year — a loss of 0.4 per cent."
Someone in this bracket
isn’t is middle class. They’re in the ninth seventh decile of disposable household income (assuming the child is aged 2-4 and council tax is £1000pa). This makes them rich upper-middle-class.
Update: amended in line with Anthony’s comment. The spin on the article is dodgy (especially as the entire fall in income was accounted for by self-reported incomes of self-employed people; coupled with higher taxation, this suggests a rise in the black economy rather than a fall in income), but the example is reasonable.