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The White House announced Thursday that 8 million people had signed up for insurance through the exchanges. That number is bigger than expected — but it only captures about half the people who have signed up for coverage through the health care law's new programs.
The Affordable Care Act's expansion of insurance coverage is sprawling, including some programs that started four years ago and some that started six months ago. And that means the health care law has a reach that extends pretty far beyond Healthcare.gov.
About 3 million people have signed up for Medicaid since October
Not all of that enrollment is attributable to the Affordable Care Act — but federal data suggests a good chunk of it is.
The health care law gives states the option to expand their Medicaid programs to cover everyone who is below 133 percent of the federal poverty line (about $15,000 for an individual). Twenty-six states and the District of Columbia have signed on to the expansion. Their Medicaid enrollment has grown much faster than the 24 states that haven't expanded their Medicaid programs.
The federal government has not provided a breakdown yet of which people signing up are newly eligible under Obamacare and who would've had access to the program regardless of the insurance expansion.
Some of the previously eligible people who signed up in the past few months might be evidence of what researchers call a "woodwork effect." These are people who could have signed up months, maybe years, ago, but only learned that they qualified for help because of the flurry of publicity around the Affordable Care Act. Whether or not to count these people as Obamacare enrollees isn't totally clear: they would have qualified for help without Obamacare but might have never known to sign up.
3.1 million young adults have gained coverage, many by joining their parents' insurance
One of the earliest parts of Obamacare to start was a new requirement that insurance plans cover dependents up to age 26. Prior to the health care law, many insurers ended coverage when a dependent had graduated from school.
The most recent estimates available suggest that about 3.1 million young adults between 19 and 25 have gained insurance coverage since this part of the health care law started in September 2010. We don't know for sure that these people were all joining their parents' coverage. But the evidence that the health law played a role is pretty compelling: young adults between 19 and 25 increased by 5.1 percentage points more than any other age group between late 2010 and 2011.
Other sources of coverage are growing, too
In advance of the individual mandate, research suggests people are signing up for employer-sponsored insurance in greater numbers — and buying individual plans off the exchanges. These are not people getting financial help to purchase insurance through Obamacare. But they are likely people being nudged in the direction of purchasing coverage because of the health law's new requirements.
Charles Gaba — the guy who knows Obamacare enrollment numbers better than anybody — estimates that between 2 to 5 million people have purchased individual policies outside the exchange.
A lot of these people are likely replacing plans they already had before Obamacare. These might be higher income people who didn't qualify for insurance subsidies and got fed up with Healthcare.gov. But this group is also likely to include some people with pre-existing conditions who, up until now, were shut out of the insurance market.
Lastly, research from the RAND Corporation suggests that about 7.2 million people have gained employer-sponsored coverage since the health law's insurance expansion began. It's hard to know here how much of this has to do with a recovering economy — where more people are gaining jobs with health benefits — and how much it reflects a greater take-up rate of insurance as people get ready to comply with Obamacare's individual mandate.
