Overall, the market for illicit drugs in Canada remains strong, and users are consuming more potent and expensive drugs. Approximately 820 tons of opium were produced in Southeast Asia during the 1984 crop year, providing about 34 percent of the drug on the Canadian market. Evidence suggests that supplies in the market have increased, entering through international airports, via the postal system, and in automobiles. Cocaine, largely from Bolivia and Columbia, has increased in availability; although prices have remained fairly stable. Air and land transport were the major means of trafficking. Chemical drugs, largely from clandestine domestic laboratories, have increased in availability and use, with lysergic acid diethylamide being the most popular. Cannabis and its derivatives were the most widely available and used drugs. Transport was primarily by air and sea. Current data reflect past trends and are expected to remain similar through 1987. Drug trafficking generates more revenue for criminal organizations than any other illegal activity, and is believed to have generated as much as $10 billion in Canada in 1984. Diversion of licit drugs also continues to be a problem. In 1984, there were significant increases in drug seizures, particularly heroin and cocaine.