Milestone in Medicare managed care.

Medicare managed care has a long history, dating back to the beginning of the Medicare program. The role and prominence of managed care in Medicare have both changed over the years; though plan participation has waxed and waned, enrollment has grown steadily. The greatest growth in Medicare managed care enrollment occurred in the middle to late 1990s, coinciding with the "managed care revolution." Enrollment growth has slowed in recent years, plan participation is declining, and the future of the program is not easy to predict.