Volkow said annual reports from a narcotics control board at the United Nations noted a 300 percent increase in the production and supply of stimulants in the United States between 1995 and 2006.

Volkow说从国家那可提尔控制中心每年的报告来看，1995至2006年，美国生产和提供的刺激性药物的数量提高了300%。