A Freedom of Information request to the Ministry of Justice found that in 2005, 1,363 people were convicted while in 2010, it was 2,135.
http://www.bbc.co.uk/news/uk-14596811
Over the past 15 years, that would be around 10 to 20 thousand convictions. Of those there were 53 paedophiles who acted in gangs.. so less than half a percent.
Interesting that.
However, more concerning is the extent of the problem:
She said last year police in England and Wales were notified of more than 23,000 offences and that recent research by the NSPCC suggested one in 20 secondary school children had been sexually assaulted.
Cheers,
Shafique