The Affordable Care Act (ACA), or “Obamacare,” has greatly improved health insurance access and coverage in Illinois, according to a new Economic Commentary [PDF] by the Illinois Economic Policy Institute. Health care coverage increased in all of the 20 most populous counties in Illinois from 2013 to 2015.

The uninsured – who are disproportionately poor, young, and non-citizens – often go long periods of time with illness or injuries before seeking medical treatment due to the high out-of-pocket costs. The Affordable Care Act was enacted with the goal of increasing the quality of, affordability of, and number of residents with health insurance. The law expanded health care coverage opportunities for most Illinoisans by creating a “marketplace” of easily-accessible insurance plans.

In Illinois, a 30-year old resident in “good” health pays between $328 and $377 per month for a health plan in the ACA-established marketplace. In a “bad year,” his or her cost would rise to $758 to $796 monthly; however, Get Covered Illinois reports that there is only a 4 percent chance a 30-year old in good health will experience a bad year. The ACA has made health care more accessible in Illinois, though costs vary by county, health, age, and other factors.

The Affordable Care Act was fully implemented in Illinois in 2014 after the Supreme Court upheld the constitutionality of the law in 2012. Since its implementation, the number of residents with health insurance has increased across the board in all of the 20 most populous counties in Illinois. Approximately 3 percent of those uninsured in Kendall County, 8 percent of those uninsured in Cook County, and 9 percent of those uninsured in St. Clair County and Macon County became insured from 2013 to 2015.

The average county-level increase in health insurance for the 20 largest Illinois counties was 7 percentage points. Today, none of the 20 most populous counties in the state has an uninsured share of the population over 10 percent. In 2013, prior to the Affordable Care Act’s implementation, only three of the top 20 counties had an uninsured rate that was under 10 percent.

One of the primary factors driving the improvements in health coverage was the expansion of Medicaid in Illinois. The number of uninsured has actually increased in some states that have not increased their Medicaid spending, including many Southern States. Over one-in-six residents remain uninsured in Texas, Florida, and Mississippi, compared to the one-in-twelve in Illinois.

Health care can be costly for low-income and middle-class households. The uninsured are more likely to postpone needed care because they cannot afford to pay for checkups, medical procedures, and medical treatment. The uninsured also frequently face severe financial hardships, facing the dilemma of either paying for health treatment or paying for living expenses, which can have consequences on national consumer demand since poorer households spend larger fractions of their incomes back into the economy.

Economic output also suffers when the poor and uninsured are sick or hospitalized. When illnesses go untreated due to lack of insurance, workers are less productive over a longer period of time. In some cases, these untreated illnesses can spread to the healthy population, causing additional missed work days and health care costs. This loss in productivity causes economic output to fall. Thus, increasing health care coverage can have positive economic impacts for Illinois.

The data are clear. The Affordable Care Act has greatly improved health insurance access and coverage in Illinois.