text: may be even lower. The number of arrestees testing positive for the first time for opiates 
  (or for both opiates and crack-cocaine) dropped from 14,750 in 2006 to 4,281 in the first 
  11 months of 2013, a fall of around 70 per cent2. Furthermore, of the new positive testers 
  in 2013, only 721 were aged 18–24.3 Though this arrestee data will capture only a 
  proportion of the true population, it does suggest that the number of new, young initiates 
  involved with crime – those who have the potential to inflict most societal harm – has 
  decreased markedly, probably just to a few thousand per year; and that this group now 
  make up a small minority of the total number of opiate/crack-cocaine users (estimated to 
  be 294,000 in 2011/12), most of whom are older, longer-term users. 
  In terms of trends in new opiate/crack-cocaine users, all available data suggest that 
  figures have dipped by at least a fifth since 2005 and have dropped hugely since the late 
  1980s and early 1990s when the opiate/crack-cocaine population in the UK grew very 
  rapidly. The current estimate works out at a rate of 0.18 per 1,000 population. During the 
  epidemic years, published estimates of new opiate/crack-cocaine users in Manchester 
  and Bolton show rates more than 11 times larger. 