Medicaid: A few people cost a whole bunch of money

No wonder this chart looks like a frown.

Just 5 percent of the most expensive people exclusively enrolled in Medicaid accounted for nearly 50 percent of all Medicaid spending on such enrollees in each year from 2009 to 2011, a new government report found.

And the most expensive 1 percent of Medicaid-only enrollees accounted for about 25 percent of all such spending in those years.

In 2011, total spending on Medicaid-only enrollees—people who are not also eligible for Medicare—was $281 billion.

The eye-opening findings by the U.S. Government Accountability Office come as the Obama administration continues to urge 21 remaining states to expand their Medicaid programs to include nearly all poor adults

Medicaid is a health-care coverage program for the poor, which is jointly run by the federal government and individual states. Different states have different criteria for who can enroll in it. In 2013, total Medicaid expenditures, which included people who were also eligible for Medicare, were about $460 billion for 72 million enrollees.

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The GAO report looked at who uses Medicaid benefits and how. It specifically focused on Medicaid enrollees who are not also eligible for Medicare, the federal program that covers primarily senior citizens.

The agency found that the most expensive 25 percent of Medicaid-only enrollees accounted for more than 75 percent of total expenditures on that population, or about $211 billion.

While the high costs from relatively few Medicaid-only enrollees drove the lions' share of the expenditures, the GAO found that the least expensive 50 percent of such people in the program accounted for less than 8 percent of total spending on such enrollees.

And about 12 percent of enrollees had no expenditures.

Read the full GAO report here.