"Federal Medicaid expenditures totaled about $267 billion in fiscal year 2013. With the expansion of Medicaid under the Patient Protection and Affordable Care Act and rising health care costs, the Congressional Budget Office projects that such expenditures will grow to about $576 billion by fiscal year 2024. GAO was asked to examine variation among states in Medicaid spending and factors that influence such spending, and state approaches to setting rates per enrollee for Medicaid managed care plans.This report examines (1) Medicaid spending per enrollee by state; (2) selected factors that influence Medicaid spending per enrollee, by state; and (3) how states account for factors that influence expected per-enrollee spending when setting rates for Medicaid managed care plans. GAO analyzed Medicaid enrollment and combined federal and state expenditure data provided by CMS for fiscal year 2008, and examined illustrative examples of factors that have been reported to influence health care spending, such as age, disability status, and scope of benefits received. GAO used 2008 data because they allowed a comparable view of spending per enrollee and factors that influence spending per enrollee-as 2008 was the most recent year for which certain data on factors influencing spending were readily available.