The way I see it is as follows:
Once you get past the lowest earners, your tax inc NI is as follows:
32% then 42% and then 52% if you earn over £150k.
Now, the 52% band only really affects employees. Why? Most self employed people can do a lot to legally reduce their taxable income and get it below the 50% band. Al Fayed only paid £1m tax on his £10m UK earnings the other year so a net tax rate of only 10%.
Yes, the top 1% may well pay 24% of the tax revenues in this country, but not necessarily because they are paying 50% tax. Al Fayed's poultry 10% tax bill of £1m probably equates to 185 people's tax on average pay.
And in the past, it has been a whole lot worse for high earners
in 1974 it was 83% plus 15% for investments and dividends which could give you a maximum rate of 98%. In 1975 they were 750,000 people in the uk who fell into this top rate of tax.
It was only in 1988 that the top rate of tax was cut from 60% to 40%.
In fact, until the 50% rate came in, the top rate of tax at 40% had been the lowest since before world war 2.
And also I think that the top percentage earners now contribute more as a percentage in tax due to more low paid people not paying tax at all and despite the higher rate of tax being much less than the seventies and thresholds increasing above RPI, there are now 7 times as many people in the top bracket for tax.