From the Summary: "Amtrak--officially the National Railroad Passenger Corporation--has been the national intercity passenger railroad since 1971, and currently serves over 500 stations on a network approximately 22,000 miles long. In some markets, such as the busy Northeast Corridor (NEC) connecting Washington, DC; New York; and Boston, it has captured a greater share of intercity passengers than domestic airlines. In other, more rural markets, some see it as a vital link to the national transportation system despite low levels of ridership. Though Amtrak is legally a private for-profit corporation, the federal government controls the company's operations. A multiyear authorization of federal funding for Amtrak was included in the Fixing America's Surface Transportation (FAST) Act of 2015 (P.L. 114-94), which expires at the end of FY2021."
CRS Report for Congress, R45942
Congressional Research Service: https://crsreports.congress.gov/