[Excerpt] The American Recovery and Reinvestment Act of 2009 (ARRA) contains provisions that are intended to boost economic activity and employment in the United States. Section 1512(e) of the law requires the Congressional Budget Office (CBO) to comment on reports filed by recipients of ARRA funding that detail the number of jobs funded through their activities. This CBO report fulfills that requirement. It also provides CBO’s estimates of ARRA’s overall impact on employment and economic output in the fourth quarter of calendar year 2011, as well as over the entire period since February 2009. Those estimates—which CBO considers more comprehensive than the recipients’ reports—are based on evidence from similar policies enacted in the past and on the results of various economic models.