"— 20,688 young people accessed specialist substance misuse services in 2011-12. This is a decrease of 1,267 individuals (5.8%) since 2010-11 and a decrease of 2,840 individuals (12.1%) since 2009-10
"— The most common routes into specialist substance misuse services were from youth offending teams (34%) and mainstream education (15%)"

Source

National Treatment Agency for Substance Misuse, "Statistics from the National Drug Treatment Monitoring System (NDTMS) - Statistics relating to young people - England, 1 April 2011– 31 March 2012" (Manchester, England: National Drug Evidence Centre, 1 November 2012), p. 2.
http://www.nta.nhs.uk/uploads…