By 2033, one in three of us will pay 40p tax rate

In its latest forecast, the OBR said that more than 9 million people could be landed with the 40 per cent tax rate, with a further 1.7 million losing 45% of their earnings.

This is on the assumption that their respective thresholds continue to rise along with inflation.

In an interview with The Telegraph, the body said: “This is because earnings are expected to rise more quickly than prices in the long term.”

Some Conservative MPs have been lobbying for tax thresholds to increase, according to the paper, as this would help the budget deficit plan to be accelerated and finish early.

They believe it’s unfair that a tax band designed for the elite is now being inflicted on so-called “middle managers”.