"The vast majority of federal cases involve an individual defendant. Over the last decade, the number of these cases has generally increased each year; however, in fiscal year 2012 the number of cases reported to the Commission fell by 2,028. This represents a decrease of 2.4 percent from fiscal year 2011.
"For the last decade, cases involving immigration, drugs, fraud, or firearms have been the most common federal criminal cases and make up the vast majority of federal felonies and Class A misdemeanors. In fiscal year 2012, these crimes accounted for 82.7 percent of all cases reported to the Commission."

Source

US Sentencing Commission, "FY 2012 Overview of Federal Criminal Cases" (Washington, DC: USSC, July 2013), p. 1.
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