The Affordable Care Act (ACA) established health insurance marketplaces where consumers can buy individual coverage. Leveraging novel credit card and bank account micro-data, we identify new enrollees in the California marketplace and measure their health spending and premium payments. Following enrollment, we observe dramatic spikes in individuals’ health care consumption. We also document widespread attrition, with more than half of all new enrollees dropping coverage before the end of the plan year. Enrollees who drop out re-time health spending to the months of insurance coverage. This drop-out behavior generates a new type of adverse selection: insurers face high costs relative to the premiums collected when they enroll strategic consumers. We show that the pattern of attrition undermines market stability and can drive insurers to exit, even absent differences in enrollees’ underlying health risks. Further, using data on plan price increases, we show that insurers largely shift the costs of attrition to non-drop-out enrollees, whose inertia generates low price sensitivity. Our results suggest that campaigns to improve use of social insurance may be more efficient when they jointly target take-up and attrition.

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This paper examines the impacts of the Affordable Care Act (ACA) – which substantially increased insurance coverage through regulations, mandates, subsidies, and Medicaid expansions – on behaviors related to future health risks after three years. Using data from the Behavioral Risk Factor Surveillance System and an identification strategy that leverages variation in pre-ACA uninsured rates and state Medicaid expansion decisions, we show that the ACA increased preventive care utilization along several dimensions, but also increased risky drinking. These results are driven by the private portions of the law, as opposed to the Medicaid expansion. We also conduct subsample analyses by income and age.

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Using a combination of subsidized premiums for Marketplace coverage, an individual mandate, and expanded Medicaid eligibility, ObamaCare has increased insurance coverage rates. The authors of this study assess the relative contributions to insurance changes of these different provisions in the law’s first full year.

Their four key findings include:

  1. Insurance coverage was only moderately responsive to price subsidies, but the subsidies were still large enough to raise coverage by almost one percent of the population; the coverage gains were larger in states that operated their own health insurance exchanges (as opposed to using the federal exchange).
  2. The exemptions and tax penalty structure of the individual mandate had little impact on coverage decisions.
  3. The law increased Medicaid coverage both among newly eligible populations and those who were previously eligible for Medicaid (the “woodwork” effect), with the latter driven predominantly by states that expanded their programs prior to 2014.
  4. There was no “crowdout” effect of expanded Medicaid on private insurance. Overall, we conclude that exchange premium subsidies produced roughly 40% of the ACA’s 2014 coverage gains, and Medicaid the other 60%, of which 2/3 occurred among previously-eligible individuals.

A new National Bureau of Economic Research Working Paper shows that workers with employer-based coverage experienced a yearly reduction in wages of $1,200 because of the mandate to expand coverage to 26-year-old children. The researchers from Stanford and Harvard also found that the wage reduction was not concentrated among those with children on their policies, showing that all workers with employer coverage are paying a price for the ObamaCare mandate.