The Public Health Service Act, Section 241 set-aside authority was originally established in 1970, when the Congress amended the Act to permit the HHS Secretary to use up to 1 percent of appropriated funds to evaluate authorized programs. Section 241 limits the base from which funds can be reserved for evaluations to programs authorized by the PHS Act. Excluded are funds appropriated for the Food and Drug Administration, the Indian Health Service, and certain other programs that are managed by PHS agencies but not authorized by the Act (e.g., HRSA's Maternal and Child Health Block Grant and CDC's National Institute for Occupational Safety and Health). 
The Appropriations Acts for 2010 and 2011 authorized the Secretary to use up to 2.5 percent of the amounts appropriated for programs authorized by the Public Health Service Act for the evaluation of these programs and purposes outlined in the appropriations bills. A total of $1,025 million and $1,001 million were available in PHS Evaluation Funds for agencies and offices in FY 2010 and FY 2011, respectively. By agency, these funds were appropriated as follows:
Administration for Children and Families (ACF) – $6 million in FY 2010 and FY 2011
Agency for Healthcare Research and Quality (AHRQ) – $397 million in FY 2010 and $372 million in FY 2011
Centers for Disease Control and Prevention (CDC) – $352 million in FY 2010 and FY 2011
Health Resources and Services Administration (HRSA) – $25 million in FY 2010 and FY 2011
National Institutes of Health (NIH) – $8 million in FY 2010 and FY 2011
Substance Abuse and Mental Health Services Administration (SAMHSA) – $132 million in FY 2010 and FY 2011
Staff components in the Office of the Secretary including the Office of the Assistant Secretary for Planning and Evaluation (ASPE), the Office of the Assistant Secretary for Health (ASH), the Office of the Assistant Secretary for Financial Resources (ASFR), the Office of the National Coordinator for Health Information Technology (ONC), and the Office of the Assistant Secretary for Preparedness and Response (ASPR) received $87 million in FY 2010 and again in FY 2011.
Funds obligated for studies in one fiscal year are typically expended during one or more future years. Therefore, a particular year's funding doesn't correlate with specific studies completed during the same year.