1. The Centers for Medicare & Medicaid Services. History: CMS’ program history [internet]. 2015 [cited 2016 Nov 26]. Available from: http://www.cms.gov/About-CMS/Agency-Information/History/index.html?redirect=/History .
2. Congressional Budget Office. The 2012 Long-term budget outlook [internet]. 2012 Jun p. 14–5. Available from: http://www.cbo.gov/sites/default/files/cbofiles/attachments/06-05-Long-Term_Budget_Outlook_2.pdf .
3. Google Public Data Explorer. World development indicators: life expectancy [internet]. [cited 2016 Nov 26]. Available from: https://www.google.com/publicdata/explore?ds=d5bncppjof8f9_&met_y=sp_dyn_le00_in&idim=country:USA:CAN:GBR&hl=en&dl=en#!ctype=l&strail=false&bcs=d&nselm=h&met_y=sp_dyn_le00_in&scale_y=lin&ind_y=false&rdim=region&idim=country:USA&ifdim=region&hl=en_US&dl=en&ind=false .
4. Mayes R. The origins, development, and passage of Medicare’s revolutionary prospective payment system. J Hist Med Allied Sci. 2007;62:21–55.
5. • The Centers for Medicare & Medicaid Services. Acute inpatient prospective payment system [internet]. 2016 [cited 2016 Nov 26]. Available from: https://www.cms.gov/Medicare/Medicare-Fee-for-Service-Payment/AcuteInpatientPPS/index.html?redirect=/acuteinpatientpps/. Webpage published by CMS outlining the system for calculating Part A payments.