Douglas Holtz-Eakin is the president of the American Action Forum and a former director of the Congressional Budget Office. He also served on President George W. Bush’s Council of Economic Advisers. With the Affordable Care Act’s insurance marketplaces beginning their third open enrollment this week, RealClearHealth talked to Holtz-Eakin about what’s working, what’s not working, what can be done today to address problems with the law, and what should be on the agenda of a new administration in 2017.

Obamacare’s third open enrollment season kicked off yesterday, beginning the next chapter in its turbulent history. Today’s post discusses what we know about Obamacare. Tomorrow’s will discuss what we don’t yet know.

States that accepted Obamacare expansions have had Medicaid enrollment increase 18 percent, and total Medicaid spending grow 17.7 percent, a recent report from Kaiser Family Foundation has shown. Alternatively, states that chose not expand under Obamacare had Medicaid enrollment increase 5.1 percent and total spending grew 6.1 percent.

This is not particularly surprising. Obamacare has certainly led to more being enrolled within Medicaid—which has been costly for taxpayers.

Among many other changes to the health care system, the ACA created an expansion of Medicaid – made optional by the Supreme Court in 2012 – funded largely by federal dollars. Thus far, 30 states and the District of Columbia have accepted the Medicaid expansion. And as should be expected, states that expanded the program have seen spending grow much faster than those that didn’t. In a recent report, the Kaiser Family Foundation found that total Medicaid spending grew nearly 18 percent in expansion states, though the state share of growth was relatively low (less than 4 percent). And while health care has remained relatively quiet as a campaign issue, Governors Kasich and Christie – both Republican presidential hopefuls – expanded Medicaid (and both have defended this expansion) in their respective states.

Beginning in FY 2014, policy changes introduced by the Affordable Care Act (ACA) have been driving Medicaid enrollment and spending growth. This report provides an overview of Medicaid enrollment and spending growth with a focus on state Fiscal Year (FY) 2015 and state Fiscal Year 2016. Findings are based on interviews and data provided by state Medicaid directors as part of the 15th annual survey of Medicaid directors in all 50 states and the District of Columbia conducted by the Kaiser Commission on Medicaid and the Uninsured (KCMU) and Health Management Associates (HMA). Information collected in the survey on policy actions taken during FY 2015 and FY 2016 can be found in the companion report. Key findings related to Medicaid enrollment and spending growth are described below.

Mercy will be the 58th rural hospital to close in the United States since 2010, according to one research program, and many more could soon join the list because of declining reimbursements, growing regulatory burdens and shrinking rural populations that result in an older, sicker pool of patients. The closings have accelerated over the last few years and have hit more midsize hospitals like Mercy, which was licensed for 75 beds, than smaller “critical access” hospitals, which are reimbursed at a higher rate by Medicare.

In 2009 and 2010 President Barack Obama and Health and Human Services Secretary Kathleen Sebelius designed and championed the largest expansion of the welfare state since the New Deal with little more than political force and broken promises. While the American people are forced to accept Obamacare until it can be repealed, the Supreme Court empowered states to accept or reject Obamacare’s Medicaid expansion. So far 20 states have said no.

Iowa’s experience with Obamacare’s Medicaid expansion has been turbulent. In 2014, state officials agreed to expand Medicaid, despite the fact that the Obama administration denied virtually all of their requests for flexibility.

Iowa’s expansion was loosely modeled after Arkansas’ Obamacare expansion. Under Iowa’s “Marketplace Choice” waiver, able-bodied adults above the poverty line would receive Medicaid benefits through Obamacare exchange plans.

The promise of free money is hard to turn down, and so when Obamacare offered the states a cheap way of expanding Medicaid, Gov. Rick Snyder found it hard to resist. Yet just a year into Michigan’s expansion, it’s not such a bargain.

In its mission to make sure more Americans have health insurance, the Affordable Care Act depended on states to expand their Medicaid programs to individuals with incomes under 138 percent of the federal poverty level.

Two reports released in the past week demonstrate a potential bifurcation in state insurance exchanges: The insurance marketplaces appear to be attracting a disproportionate share of low-income individuals who qualify for generous federal subsidies, while middle- and higher-income filers have generally eschewed the exchanges.

On Wednesday, the consulting firm Avalere Health released an analysis of exchange enrollment. As of the end of the 2015 open-enrollment season, Avalere found the exchanges had enrolled 76% of eligible individuals with incomes between 100% and 150% of the federal poverty level—between $24,250 and $36,375 for a family of four. But for all income categories above 150% of poverty, exchanges have enrolled fewer than half of eligible individuals—and those percentages decline further as income rises. For instance, only 16% of individuals with incomes between three and four times poverty have enrolled in exchanges, and among those with incomes above four times poverty—who aren’t eligible for insurance subsidies—only 2% signed up.

The Avalere results closely mirror other data analyzed by the Government Accountability Office in a study released last Monday. GAO noted that three prior surveys covering 2014 enrollment—from Gallup, the Commonwealth Fund, and the Urban Institute—found statistically insignificant differences in the uninsured rate among those with incomes above four times poverty, a group that doesn’t qualify for the new insurance subsidies.