Cannabis: police seizures show drop in drug's strength / Guardian, 28 August 2008
http://www.guardian.co.uk/politics/2008/aug/28/drugspolicy.justice?gusrc=rss&feed=politics
"The potency of cannabis gathered in police seizures has dropped, new official data reveals, casting doubt on one of the government's key arguments for reclassifying the drug from class C to class B. Figures collected by the Forensic Science Service and seen by guardian.co.uk show that the potency of herbal cannabis, which includes the strong "skunk" strain, has dropped from 12.7% to 9.5% since 2004, when it was first moved from class B to the less serious class C."