EPA enforcement data show that the amount of monetary results EPA regions achieve from concluded enforcement cases varies from year to year and from region to region. While the number of enforcement cases concluded for FYs 2006 through 2011 remained relatively constant, the overall monetary results varied. The variations are linked to when and where in the nation a few large cases are concluded. These few large cases can result in unusually large monetary results in any given year. National Enforcement Initiatives (NEIs) set by EPA's Office of Enforcement and Compliance Assurance drove the majority of these large cases. In FY 2010, Region 7 concluded two enforcement cases with large monetary results. Both cases were pursued under EPA's NEIs. The two cases accounted for 24 percent of all of EPA's monetary enforcement results for FY 2010 and 98 percent of Region 7's monetary results for FY 2010. Region 7's results typically fell in the middle of the 10 regions. We found that from FYs 2006 through 2011, Region 7's enforcement results, regulated facilities, and staff allocated to enforcement were proportional with each other. Large cases took several years to close and relied on coordination with the U.S. Department of Justice, companies, and courts, which meant that EPA did not have full control over the year in which a case was settled.