Department of Homeland Security: H-2B Usage and Recommendations (Fiscal Year 2016 Report to Congress) [open pdf - 744KB]
"DHS has compiled this report on H-2B temporary nonagricultural worker petition usage and recommendations with information provided by the Department of State. This report includes data for the past 10 fiscal years and is current through November 30, 2015. The Senate Committee directed USCIS [U.S. Citizenship and Immigration Services] to study the actual usage of H-2B visas in relation to the number of applications granted and to provide recommendations on how to ensure systematically that the number of visas granted is aligned more closely with the number of visas used by employers."
U.S. Department of Homeland Security: http://www.dhs.gov/