"The most recent estimates of problem drug use in England were published in 2011 (Hay et al. 2011; see UK Focal Point Report 2011) showing that there were an estimated 306,150118 opiate and/or crack cocaine users in 2009/10. New national and local estimates of the prevalence of opiate and/or crack cocaine use (OCU) are being calculated for 2010/11 with separate estimates for opiate use, crack cocaine use and injecting drug use. It is anticipated that the results will be available in 2013."

Source

UK Focal Point on Drugs, "United Kingdom Drug Situation 2012 Edition: Annual Report to the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA)" (London, England: UK Government, Department of Health, October 31, 2012), p. 84.
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