From 2001 through 2008, New York’s Medicaid managed care enrollment tripled, increasing from just over 729,000 to approximately 2.2 million enrollees. Most of the growth occurred between 2001–2004, before leveling off, and then beginning to grow again over the last year. The early growth spurt can largely be attributed to the implementation of mandatory enrollment in New York City. The most recent growth spurt is due largely to mandatory enrollment of the SSI population which began in 2006 and the implementation of mandatory enrollment in a number of upstate counties. Enrollment in NYC as of July 2008 was 1.6 million, and 603,000 in the rest of New York State.

Since 2001, Child Health Plus (CHP) enrollment is down 24% across the State, down 50% in NYC, but up 12% in the rest of the State. Recent figures show a rebound within the last three months of 2008, for a total enrollment of more than 365,000 enrollees in NYS: 143,000 in NYC and 222,000 in the rest of the State.
     
Family Health Plus began enrollment in late 2001 and very quickly grew to more than 512,000 members by 2005. Enrollment has been relatively flat since then with some monthly fluctuation. July 2008 FHP enrollment was 518,000, with 384,000 in NYC and 134,000 in the rest of the State.
     
Since passage of the Medicare Prescription Drug, Improvement, and Modernization Act of 2003 (MMA), Medicare managed care (now known as Medicare Advantage) enrollment has grown significantly at both national and local levels. Enrollment has grown to more than 775,000 in New York State as of July 2008, increasing by almost 100,000 (14%) in the last year alone. Since 2001, Medicare Advantage enrollment grew by 64% in the State, with most of that growth occurring since 2004. Medicare advantage enrollment grew by 56% in NYC to more than 337,000 members, and by 70% in the rest of the State to more than 437,000 enrollees.