I am looking for historical data on HMO enrollment (nationwide), from
1980 to 2000 (and/or later, if available). More specifically, I'm
trying to find out what percentage of enrollees were in nonprofit
plans and what percentage were in for-profit plans. Ideally, I'd like
to find data in 5-year increments (1980, 1985, 1990, etc) plus the
latest figure available but bare minimum is two data points, comparing
either figures for 1980 or 1985 with figures for 1995 or 2000. Please
include reference information and/or the website address where you
found the information, so I can cite it properly. I've
searched several publications from NCHS and other federal health
agencies, but hven't found anything yet. I'm sure the data must be out
there, but I'm obviously not looking in the right places. One other
point: please specify if the data includes Medicare and/or Medicaid
enrollees (if known).