.
It did got down. The 50p rate was introduced in April 2010 as reflected in the 2010-11 figures below, from the HMRC. Look what happened.
Now some of the tax in 2009-10 was due to people hurriedly paying themselves more in that year, in order to avoid the 50% in the following year**. So the effect is exaggerated. But look at 2008-09 as well, still much higher (with a max 45% rate) than 2010-11 with the 50%. Even in 2011-12, at 50% it was still bringing in less.
** which kind of proves my point: A lot of wealthy people have flexibility in their earnings and can rearrange their affairs in order to reduce their tax bills, if rates get too penal.
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