Estimated Potential US Retail Hemp Market

"Retail sales of imported hemp products exceeded $70 million in the United States in 2006.62 Given hemp’s wide-ranging utility, supporters of domestic cultivation estimate that it would create a $300 million dollar industry.63"

Source: 

Kolosov, Christine A. Evaluating the Public Interest: Regulation of Industrial Hemp under the Controlled Substances Act. UCLA Law Review. Los Angeles, CA: UCLA School of Law, 2009.