EXHIBIT 1.

Medicare Shared Savings Program ACO cohorts’ initial average baseline spending deviation and subsequent changes over time attributable to ACO-level exit and within-ACO participant list reconfiguration.

Source/Notes: SOURCE Authors’ analysis of CMS MSSP Provider-level Research Identifiable Files, Medicare claims, and MD-PPAS data. NOTES Points represent average baseline risk-adjusted regional spending deviation based on ACOs’ initial participant list configuration, weighted by number of attributed beneficiaries, and lines represent net changes within a cohort due to ACO-level exit and within-ACO participant list reconfiguration over time; For example, an ACO cohort with no exits and no participant list changes would be represented as straight horizontal lines, shifted vertically depending on its initial baseline risk-adjusted regional spending deviation.