 It is the most popular Wisconsin-based Medicare supplement plan in the state, with more than 42,000 members, based on enrollment data submitted to the National Association of Insurance Commissioners, 2015.In 1966, the year Medicare was established, WPS was named the Medicare administrator for the state of Wisconsin.WPS is currently the Medicare Administrative Contractor for Jurisdiction 5 in Iowa, Kansas, Missouri, and Nebraska, as well as for Jurisdiction 8 in Indiana and Michigan.