"Preliminary 2008 availability and seizure data indicate a strengthening in domestic methamphetamine availability and domestic methamphetamine production, and an increase in the flow of methamphetamine into the United States from Mexico—most likely attributable to the efforts of methamphetamine producers in both countries to reestablish the methamphetamine supply chain in the face of disruptions and shortages that began occurring in early 2007. Throughout 2007 methamphetamine availability decreased in U.S. drug markets, causing instability in the methamphetamine supply chain. Prior to 2007, U.S. drug markets relied on the strong flow of methamphetamine produced in Mexico, a supply system established in 2005 and strengthened in 2006. However, ephedrine and pseudoephedrine restrictions in Mexico resulted in a decrease in methamphetamine production in Mexico and reduced the flow of the drug from Mexico to the United States in 2007 and from January through June 2008."

Source

National Drug Intelligence Center, "National Methamphetamine Threat Assessment 2009" (Johnstown, PA: US Dept. of Justice, Dec. 2008), p. 1.
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