Changes in Marketplace Competition and Television Advertising by Insurers
Study Design: This study links data capturing Marketplace participation (CMS Qualified Health Plan Landscape files) by county and health insurance advertising (Kantar Media/Campaign Media Analysis Group) by media market for the 2014 through 2018 open enrollment periods.
Methods: We used population-weighted county fixed effects models to estimate the relationship between year-over-year changes in Marketplace competition and changes in (1) total private advertising and (2) advertising per insurer.
Results: Going from multiple insurers to a single insurer resulted in 465 fewer private ads aired within a county during open enrollment (P < .01), a 17% to 38% reduction. Losing monopoly status is associated with a drop in advertising of 452 airings per insurer (P < .01), and becoming a monopolist is associated with 293 more airings per insurer (P < .01).
Conclusions: Insurers are not replacing the decline in government-sponsored advertising. We find that insurers behave as if they are responding to strategic incentives, advertising more when they become a monopolist but not filling the hole left by their former competitor, which has implications for the volume of messages seen by consumers.
Am J Manag Care. 2021;27(8):323-328
Insurers are not picking up the slack as government-sponsored advertising has decreased and are instead behaving in ways that benefit themselves strategically.
- Reductions in Health Insurance Marketplace competition leading to a monopoly county resulted in a loss of between 17% and 38% of the population-weighted average of private advertising during open enrollment.
- We find no relationship between a county becoming competitive (going from 1 insurer to 2 or more insurers) and changes in total private advertising.
- This implies a potential 1-sided effect, with total private advertising dropping when markets become a monopoly but not necessarily increasing when markets become competitive.
The state and federally run health insurance exchanges established under the Affordable Care Act (ACA), collectively referred to as the Health Insurance Marketplace, entered their eighth open enrollment period at the end of 2020. Although the ACA and its Marketplace have seen their share of challenges—from insurers leaving the Marketplace, resulting in counties with no options, to rising unsubsidized premiums and threats of repeal—it nonetheless continues to be a crucial source of coverage for millions of Americans who do not qualify for employer-sponsored coverage or Medicaid.1-5 During crises, like the COVID-19 pandemic, the Marketplace can play a significant role in providing a source of coverage that is decoupled from work for those households that have too high of an income to qualify for Medicaid but otherwise would lack access to health insurance coverage.6
Given the continued significance of the Marketplace, it is important to consider the ways in which Americans receive information about these health insurance options. The Trump administration ended television advertising and severely cut funding for enrollment assistance for the Marketplace prior to the 2018 open enrollment period, cuts that persisted until the administration’s end in 2020.7 Federal officials in the Trump administration noted “diminishing returns” to television advertising, in opposition to their own leaked internal research, arguing that a shift toward online advertising was a better use of resources as the novelty of the ACA and Marketplace as part of the American health insurance landscape had worn off.7,8 This argument that the public is broadly aware of the Marketplace was repeated in a 2019 Congressional hearing, in which it was asserted by some that insurers could fill the hole that states and the federal government have left as their advertising declined or disappeared.9 Although one-fourth of Marketplace enrollees for 2020 were new customers (suggesting they had at least some awareness), millions of Americans each year may transition into eligibility for subsidized Marketplace coverage who were never previously enrolled in it, including by aging out of parental coverage, losing employer-sponsored coverage through job loss or transition, starting a small business, or gaining enough income to lose Medicaid eligibility.10 There are millions of uninsured adults eligible for Marketplace subsidies who could be covered at little to no cost to them.11 Further, surveys consistently demonstrate confusion on the part of the public about the continued existence of the Marketplace.12-14 Former marketing officials for HealthCare.gov have come out publicly to dispel the notion that government advertising is no longer necessary, citing the relative efficiency of their advertising spending relative to that of insurers.15-17 Insurers, now the dominant television advertiser,18 have the role of informing consumers about this market. However, insurers face different incentives than the federal government in choosing where to allocate their television advertising resources. They may choose to focus on the most highly populated areas or areas with more profitable populations net of risk adjustment to maximize expected profits rather than focusing on areas with higher populations of sick, or expensive to insure, unenrolled individuals who may benefit the most from information about and access to health insurance coverage.
A growing body of research has examined the effects of multiple sources of television advertising on enrollment in the ACA health insurance exchanges, commonly known as the Marketplace.18-22 Advertising is important because despite the maturing nature of this market, confusion and uncertainty among consumers have increased amid changing implementation and political upheaval. The evidence on effects of privately sponsored advertising in particular (distinct from federal or state ads or the overall volume of advertising) has been lackluster thus far, with several studies showing null or even negative effects of private insurer ads on Marketplace enrollment.18-22 In a study of the original state-based exchange in Kentucky, only a single-digit percentage of information-seeking behavior (6% of page views and unique visitors to the website) by potential enrollees was attributable to insurer advertising and seemed to draw applications off-exchange (–11% total and –30% of web-based applications, based on counterfactual predictions),19 meaning that applications through the state Marketplace itself went down and consumers were presumably enrolling directly through insurer websites. In 2 national studies of the first open enrollment period for the Marketplace (2014), one found no relationship of private insurer advertising with the county-level uninsured rate and the other found no relationship with individual-level odds of having shopped for or enrolled in a Marketplace plan.20,21 However, the most comprehensive study of Marketplace advertising published to date, on states using the federal platform (HealthCare.gov) during the 2015 through 2018 open enrollment periods, found a positive association of insurer advertising with county-level Marketplace enrollment rate (average marginal effect of 7.2 enrollees per 100,000 younger than 65 years per additional 100 ad airings), although the estimated magnitude of the dose-response relationship was much smaller than that of state and federal advertising.18 A recent working paper has found that insurer advertising has a positive effect on its own enrollment, but without spillovers to other Marketplace insurers, and is less effective than federal advertising.22
Independent of our evolving knowledge of the relative effectiveness of different types of health insurance advertising on enrollment in the Marketplace, no studies have yet explored whether and how insurers are responding strategically in their advertisement investments to changes in Marketplace competition. There is clearly still a need to inform the public about the Marketplace and desire by insurers to increase their enrollment and market share in the regions in which they operate. With the changes in market entry and exit in the early years of the Marketplace, there is ample variation with which to observe whether insurers as a whole are filling the gap left by reductions in state and federal government advertising and how they respond when facing changes in competition. Insurers with a monopoly in a county can change the size and composition of the risk pool through both pricing and outreach strategies, but their approach may change in the face of another insurer entering that market.23,24 This study provides the first evidence on how insurers are altering their marketing in response to changes in competitive pressure over time. This has important implications not only for a better understanding of insurer behavior but also for the potential educational value of insurance messages reaching consumers in light of the near-disappearance of government-sponsored Marketplace advertising in recent years.
This study links data from 2 primary sources—data capturing Marketplace participation by county and health insurance advertising data by media market—to understand how insurers altered their advertising investments in response to changes in the competitive environment. We used the CMS Qualified Health Plan Landscape files to find the number of insurers participating (unique Health Insurance Oversight System identifiers) in the Marketplace for each county–open enrollment period for the 2014 through 2018 open enrollment periods.25 We captured year-over-year changes in county-level insurer competition—from 2 or more insurers to 1 insurer and from 1 insurer to 2 or more insurers. This was paired with local broadcast and national cable advertising data from Kantar Media/Campaign Media Analysis Group, obtained in collaboration with the Wesleyan Media Project, to measure the total number of Marketplace-focused television ad airings by private (ie, insurance companies, brokers), federal government, and state government sponsors for each media market–open enrollment period, similar to previous studies.18-22
For the data on health insurance advertising, individual ads were viewed and coded based on the product category targeted: Marketplace or other private (individual or group market) coverage, Medicaid, and Medicare. For private advertising, we measure both the total volume and mean volume of ad airings per participating insurer (eg, total private ad airings for 2018 divided by number of participating insurers) for each county–open enrollment period. For state ads, we also distinguished between ads aired for the state in which the county is located and ads aired for another state, as some media markets cross state lines (for instance, the Minneapolis media market reaches counties located in Wisconsin). Like all previous studies,18-22 we use the count of ads aired as our outcome due to cost and data availability limitations. Gross ratings points (GRPs) theoretically do a better job of capturing potential reach of advertising; however, the correlation between GRPs and airing counts is very high, with a study of the 2004 presidential campaign finding a correlation between them of 0.95.26
We used a crosswalk to uniquely assign each county to its corresponding media market to allow Marketplace participation data (at the county level) and advertising data (at the media market level) to be merged. We also derived the mean county population younger than 65 years during the study period (2013 to 2017) using data from the Census Bureau Population Estimates Program to allow for population weighting of our analysis.27
Our analysis focuses on the 34 states that used the federal Marketplace platform (HealthCare.gov) exclusively during the 2014 to 2018 open enrollment periods, resulting in 2509 counties with complete data (Figure 1). We describe population-weighted trends in Marketplace advertising volume by sponsor type (private, federal, state–own, state–other) for the included counties over the study period and assess whether the volume of private advertising per participating insurer is changing over time. We use population-weighted county fixed effects models to estimate the relationship between changes in Marketplace competition on changes in (1) total private advertising and (2) advertising per participating insurer. These models include indicators for year-over-year changes in Marketplace competition (from 2 or more insurers to 1 insurer, from 1 insurer to 2 or more insurers), year-over-year changes in federal and state government advertising, and open enrollment period fixed effects. The population weighting ensures that the estimation incorporates counties proportionally rather than allowing smaller counties to drive our results as much as a county several times larger, accounting for the fact that more populous counties are going to drive advertising volumes within a media market. Standard errors were clustered at the media market level to match the level at which advertising is purchased. Our analyses were conducted in Stata version 16.1 (StataCorp).
The population-weighted county mean for private ad airings for the included states fell from the 2014 (2619 airings) and 2015 (2734 airings) open enrollment periods to 2017 (1236 airings) before a slight but statistically insignificant rebound in the 2018 (1247 ads) open enrollment period (Figure 2). Population-weighted county mean federal advertising fell from a level that nearly matched that of private sponsors during the 2014 open enrollment period (2600 ads) to zero in the 2018 open enrollment period, after the Trump administration chose to reduce funding allocated to Marketplace promotion by 90% and focus on digital advertising.28 Private advertising per Marketplace insurer similarly declined over the first 3 open enrollment periods, by 18% (from 2014 to 2015) and 34% (from 2015 to 2016), before rebounding in 2017 and 2018 to levels that were still below those of 2015 (607 vs 647 ads per insurer) (Figure 3).
Our regression results (Table) show how private advertising volumes change in response to changes in Marketplace competition and advertising by government sponsors. Compared with no change in competition, going from multiple insurers to a single insurer resulted in 465 fewer private ads aired in total within a county during open enrollment (P < .01), which corresponds to between 17% and 38% of the county-level weighted mean of total private ad airings during the 5 open enrollment periods included. We find no relationship between a county becoming competitive (going from 1 insurer to 2 or more insurers) and changes in total private advertising. This implies a 1-way effect, with total private advertising dropping when markets become a monopoly but not necessarily increasing when markets become competitive. The relationships between changes in total private advertising and government-sponsored advertising were small, indicating that insurers are not responding to changes in government-sponsored advertising at the county level. Only changes in state Marketplace advertising from the state in which a particular county was located had a significant association with changes in private advertising, although the magnitude was small, with 0.2 fewer private ads for each additional state ad aired compared with the prior open enrollment period (P < .05).
On a per-insurer basis (Table), losing monopoly status is associated with a drop of 452 ad airings per insurer in county-level advertising during an open enrollment period (P < .01). Conversely, a market becoming a monopoly is associated with an increase of 293 ad airings per insurer during open enrollment (P < .01), indicating that the remaining insurer fills some of the gap left by its former competitor but not all. The relationships between changes in government-sponsored advertising and both total private and per-insurer advertising were small or not significant.
Marketplace competition fell sharply over the initial years of implementation, from approximately 80% of counties having at least 3 participating insurers in 2015 and 2016 to approximately 36% in 2018.29 As such, whether and how insurers’ marketing efforts respond to these changes have implications for consumer awareness about the availability of coverage and financial assistance. Our study found that insurers are behaving as if they are responding to strategic incentives, advertising more when they become a monopolist but not filling the hole left by their former competitor. There are 2 explanations for this: (1) assumptions about consumers with no alternatives and (2) maximizing marginal revenue. An insurer with a newfound monopoly in a given county knows that it will get all the Marketplace enrollment in that year, so it has little incentive to invest in making up the hole in advertising left by its former competitor, greatly increasing its market share without a proportional expansion of administrative costs and marketing. Disruptions in coverage from an insurer exiting a market may also shrink the enrollment pool.30 Newly monopolistic insurers may be reluctant to maximize enrollment because individuals who transition to a new insurer may increase their use of care in the short term, costs that may not be fully offset by risk adjustment revenue. However, insurers do gain incremental revenue from each additional enrollee given the minimum medical loss ratios (of either 80% or 85%) established by the ACA, which provides an incentive to increase enrollment regardless of the level of competition. They can use advertising dollars to encourage those with a lower propensity to enroll, like younger and healthier people who are cheaper to cover, by educating them about benefits like free preventive services and availability of premium subsidies and also pull in those who no longer would be automatically reenrolled.31,32 Increased competition in the Marketplace would also mean increased competition for limited advertising slots, which could raise prices and result in lower advertising per insurer even if ad spending remained the same.
This study has several limitations to keep in mind when considering our findings. We assume that insurers know the market structure of each county (or county within a larger rating area) before they place their advertising orders. Marketplace plans are typically submitted in May or June of each year, with contracts signed in late September before the open enrollment period starts in the fall for coverage that begins on January 1 of the following year. However, not all county monopolies would have been anticipated because several insurers have withdrawn from markets late in the rate filing process when their competitors’ advertising plans may have already been finalized. Also, some insurers took the opportunity of filling bare counties (those without a participating insurer) where there may not have been the time or capability to change advertising strategies.33 We examine the relationship between market competition and advertising volumes without incorporating information on the larger dynamics of entry and exit decisions in the Marketplace, in which claims experience, regulatory changes, and other factors may play a role in individual insurers deciding whether to participate in a given county or in the Marketplace at all.34,35 Another limitation relates to the advertising data. Local broadcast television advertising is not targeted to a specific county but rather to a media market as a whole. In this study, all counties are uniquely assigned to a single media market, and thus advertising doses are constant across all counties within each market for each open enrollment period. We weighted our models by population to allow counties to contribute proportionally to our estimates, minimizing the influence of smaller counties that are likely not the primary target of insurer advertising. Finally, although the insurer competition data are restricted to Marketplace participants, the advertising data encompass insurer advertising for any private non-Medicare and non-Medicaid health insurance product—which includes Marketplace and other ACA-compliant plans but also potentially employer and non–ACA-compliant plans (eg, short-term plans, limited duration plans). Insurers may also engage in marketing outside of television (eg, billboards, radio, digital advertising, community events) to focus on specific counties, which we do not observe.
These findings tell an important story about the differing roles of government and insurers in informing consumers about health insurance options. Although total private advertising nationwide seemed to rebound during the 2018 open enrollment period as the federal government ended its television campaign,28 the story looks considerably different at the county level. Insurers are generally not replacing marketing 1-for-1 as government-sponsored advertising and specific mentions of the Marketplace have decreased, and they are instead behaving in ways that benefit themselves strategically. This has implications not only for the volume of messages seen by consumers to educate them about open enrollment and financial assistance, but also for the strength and competitiveness of the Marketplace in the face of ongoing political volatility. Private health insurance advertising rarely communicates the explicit role of government in the availability of individual market coverage.18,36 We know not only that consumers respond to the perceived benefit of public programs, like the Marketplace, but that partisanship and political messaging also play a key role in participation and creating policy feedback.3,37-41 In spite of the health and economic effects brought on by the COVID-19 pandemic, reports suggest that President Trump had not abandoned his desire to repeal the ACA.41 The Biden administration has reversed course, opening a broad special enrollment period in early 2021 with significant new investments in marketing and community outreach.42,43 At a time when health insurance disruption has spiked to levels never before seen in modern history, understanding the composition, effects, and strategic interactions among stakeholders in the Marketplace is more important than ever.
Author Affiliations: Department of Health Law, Policy, and Management, School of Public Health, Boston University (PRS), Boston, MA; Margolis Center for Health Policy, Duke University (DMA), Durham, NC; Wesleyan Media Project (LMB, EFF) and Government Department (EFF), Wesleyan University, Middletown, CT; Division of Health Policy and Management, School of Public Health, University of Minnesota (SEG), Minneapolis, MN.
Source of Funding: The authors acknowledge Wesleyan University and the Robert Wood Johnson Foundation for support to establish the advertising data infrastructure used in this study (State Health Access Reform Evaluation, 72179). This work has also been supported in part by the Russell Sage Foundation (1808-08181).
Author Disclosures: Dr Gollust was a consultant to the nonprofit organization United States of Care for a project on public engagement in health policy in 2019. The remaining authors report no relationship or financial interest with any entity that would pose a conflict of interest with the subject matter of this article.
Authorship Information: Concept and design (PRS, DMA, LMB, EFF, SEG); acquisition of data (PRS, LMB, EFF); analysis and interpretation of data (PRS, DMA, SEG); drafting of the manuscript (PRS); critical revision of the manuscript for important intellectual content (DMA, LMB, EFF, SEG); statistical analysis (PRS); obtaining funding (EFF, SEG); and administrative, technical, or logistic support (LMB).
Address Correspondence to: Paul R. Shafer, PhD, Department of Health Law, Policy, and Management, School of Public Health, Boston University, 715 Albany St, Boston, MA 02118. Email: email@example.com.
1. Health insurance exchanges 2020 open enrollment report. CMS. April 1, 2020. Accessed June 22, 2020. https://www.cms.gov/files/document/4120-health-insurance-exchanges-2020-open-enrollment-report-final.pdf
2. Fehr R, Kamal R, Cox C. Insurer participation on ACA Marketplaces, 2014-2020. Kaiser Family Foundation. November 23, 2020. Accessed July 13, 2021. https://www.kff.org/private-insurance/issue-brief/insurer-participation-on-the-aca-marketplaces-2014-2021/
3. Anderson D, Shafer P. The Trump effect: postinauguration changes in Marketplace enrollment. J Health Polit Policy Law. 2019;44(5):715-736. doi:10.1215/03616878-7611623
4. Peterson MA. The ACA a decade in: resilience, impact, and vulnerabilities. J Health Polit Policy Law. 2020;45(4):595-608. doi:10.1215/03616878-8255517
5. Jones DK, Gordon SH, Huberfeld N. Have the ACA’s exchanges succeeded? it’s complicated. J Health Polit Policy Law. 2020;45(4):661-676. doi:10.1215/03616878-8255577
6. Garrett B, Gangopadhyaya A. How the COVID-19 recession could affect health insurance coverage. Urban Institute. May 4, 2020. Accessed June 22, 2020. https://www.urban.org/research/publication/how-covid-19-recession-could-affect-health-insurance-coverage/view/full_report
7. Kliff S. Trump is slashing Obamacare’s advertising budget by 90%. Vox. August 31, 2017. Accessed June 22, 2020. https://www.vox.com/2017/8/31/16236280/trump-obamacare-outreach-ads
8. Cohn J, Young J. Emails show Trump administration was told Obamacare ad cuts could hurt enrollment. HuffPost. Updated December 17, 2018. Accessed June 22, 2020. https://www.huffpost.com/entry/trump-verma-obamacare-advertising-cut_n_5c115061e4b084b082ff8dba
9. Oversight hearing: impact of the administration’s policies affecting the Affordable Care Act. House Committee on Appropriations. February 6, 2019. Accessed June 22, 2020. https://appropriations.house.gov/legislation/hearings/oversight-hearing-impact-of-the-administration-s-policies-affecting-the
10. Graves JA, Nikpay SS. The changing dynamics of US health insurance and implications for the future of the Affordable Care Act. Health Aff (Millwood). 2017;36(2):297-305. doi:10.1377/hlthaff.2016.1165
11. Garfield R, Orgera K, Damico A. The coverage gap: uninsured poor adults in states that do not expand Medicaid. Kaiser Family Foundation. January 21, 2020. Accessed October 30, 2020. https://www.kff.org/medicaid/issue-brief/the-coverage-gap-uninsured-poor-adults-in-states-that-do-not-expand-medicaid/
12. Dropp K, Nyhan B. One-third don’t know Obamacare and Affordable Care Act are the same. New York Times. February 7, 2017. Accessed October 30, 2020. https://www.nytimes.com/2017/02/07/upshot/one-third-dont-know-obamacare-and-affordable-care-act-are-the-same.html
13. Durkheimer M. Does Obamacare still exist? Forbes. January 29, 2018. Accessed October 30, 2020. https://www.forbes.com/sites/michaeldurkheimer/2018/01/29/does-obamacare-still-exist
14. Kirzinger A, Wu B, Brodie M. Kaiser Health Tracking Poll – February 2018: health care and the 2018 midterms, attitudes towards proposed changes to Medicaid. Kaiser Family Foundation. March 1, 2018. Accessed October 30, 2020. https://www.kff.org/health-reform/poll-finding/kaiser-health-tracking-poll-february-2018-health-care-2018-midterms-proposed-changes-to-medicaid/
15. Lodes L. I ran ACA outreach under Obama. Trump’s funding cuts could ruin the health care law. Vox. September 15, 2017. Accessed June 22, 2020. https://www.vox.com/the-big-idea/2017/9/12/16294784/aca-outreach-advertising-sabotage-funding
16. Peck J. Why marketing matters for HealthCare.gov. Medium. February 7, 2018. Accessed June 22, 2020. https://medium.com/get-america-covered/why-marketing-matters-for-healthcare-gov-46d19534a287
17. Peck J. Congressional oversight hearing on the impact of the administration’s policies affecting the Affordable Care Act. House Appropriations Subcommittee on Labor, Health and Human Services. February 6, 2019. Accessed June 22, 2020. https://docs.house.gov/meetings/AP/AP07/20190206/108858/HHRG-116-AP07-Wstate-PeckJ-20190206.pdf
18. Shafer PR, Anderson DM, Aquino SM, Baum LM, Fowler EF, Gollust SE. Competing public and private television advertising campaigns and Marketplace enrollment for 2015 to 2018. RSF. 2020;6(2):85-112. doi:10.7758/RSF.2020.6.2.04
19. Shafer PR, Fowler EF, Baum LM, Gollust SE. Television advertising and health insurance Marketplace consumer engagement in Kentucky: a natural experiment. J Med Internet Res. 2018;20(10):e10872. doi:10.2196/10872
20. Karaca-Mandic P, Wilcock A, Baum LM, et al. The volume of TV advertisements during the ACA’s first enrollment period was associated with increased insurance coverage. Health Aff (Millwood). 2017;36(4):747-754. doi:10.1377/hlthaff.2016.1440
21. Gollust SE, Wilcock A, Fowler EF, et al. TV advertising volumes were associated with insurance Marketplace shopping and enrollment in 2014. Health Aff (Millwood). 2018;37(6):956-963. doi:10.1377/hlthaff.2017.1507
22. Aizawa N, Kim YS. Government advertising in market-based public programs: evidence from Health Insurance Marketplace. SSRN. August 10, 2020. Accessed October 30, 2020. doi:10.2139/ssrn.3434450
23. Drake C, Abraham JM. Individual market health plan affordability after cost-sharing reduction subsidy cuts. Health Serv Res. 2019;54(4):730-738. doi:10.1111/1475-6773.13190
24. Trachtman S. When state policy makes national politics: the case of “Obamacare” Marketplace implementation. J Health Polit Policy Law. 2020;45(1):111-141. doi:10.1215/03616878-7893591
25. FFM QHP landscape files: health and dental datasets for researchers and issuers. HealthCare.gov. Accessed June 22, 2020. https://www.healthcare.gov/health-and-dental-plan-datasets-for-researchers-and-issuers/
26. Franz MM, Ridout TN. Political advertising and persuasion in the 2004 and 2008 presidential elections. Am Polit Res. 2010;38(2):303-329. doi:10.1177/1532673X09353507
27. County population by characteristics: 2010-2019. US Census Bureau. Accessed June 22, 2020. https://www.census.gov/data/tables/time-series/demo/popest/2010s-counties-detail.html
28. Gollust SE, Baum LM, Barry CL, Fowler EF. Health insurance television advertising content and the fifth open enrollment period of the Affordable Care Act Marketplaces. Health Affairs. November 8, 2018. Accessed June 22, 2020. https://www.healthaffairs.org/do/10.1377/hblog20181107.968519/full/
29. Griffith K, Jones DK, Sommers BD. Diminishing insurance choices in the Affordable Care Act Marketplaces: a county-based analysis. Health Aff (Millwood). 2018;37(10):1678-1684. doi:10.1377/hlthaff.2018.0701
30. Crespin D, DeLeire T. As insurers exit Affordable Care Act Marketplaces, so do consumers. Health Aff (Millwood). 2019;38(11):1893-1901. doi:10.1377/hlthaff.2018.05475
31. Fiedler M. New data on sign-ups through the ACA’s Marketplaces should lay “death spiral” claims to rest. Brookings. February 8, 2017. Accessed June 22, 2020. https://www.brookings.edu/blog/usc-brookings-schaeffer-on-health-policy/2017/02/08/new-data-on-sign-ups-through-the-acas-marketplaces-should-lay-death-spiral-claims-to-rest/
32. Drake C, Anderson DM. Association between having an automatic reenrollment option and reenrollment in the Health Insurance Marketplaces. JAMA Intern Med. 2019;179(12):1725-1726. doi:10.1001/jamainternmed.2019.3717
33. Sanger-Katz M. Obamacare’s bare county problem looks solved, for now. New York Times. August 15, 2017. Accessed June 22, 2020. https://www.nytimes.com/2017/08/15/upshot/obamacares-bare-county-problem-looks-mostly-solved-for-now.html
34. Drake C, Anderson DM. Terminating cost-sharing reduction subsidy payments: the impact of Marketplace zero-dollar premium plans on enrollment. Health Aff (Millwood). 2020;39(1):41-49. doi:10.1377/hlthaff.2019.00345
35. Anderson DM, Abraham JM, Drake C. Rural-urban differences in individual-market health plan affordability after subsidy payment cuts. Health Aff (Millwood). 2019;38(12):2032-2040. doi:10.1377/hlthaff.2019.00917
36. Barry CL, Bandara S, Arnold KT, et al. Assessing the content of television health insurance advertising during three open enrollment periods of the ACA. J Health Polit Policy Law. 2018;43(6):961-989. doi:10.1215/03616878-7104392
37. Sances MW, Clinton JD. Who participated in the ACA? gains in insurance coverage by political partisanship. J Health Polit Policy Law. 2019;44(3):349-379. doi:10.1215/03616878-7366988
38. Campbell AL. The Affordable Care Act and mass policy feedbacks. J Health Polit Policy Law. 2020;45(4):567-580. doi:10.1215/03616878-8255493
39. Trachtman S. Polarization, participation, and premiums: how political behavior helps explain where the ACA works, and where it doesn’t. J Health Polit Policy Law. 2019;44(6):855-884. doi:10.1215/03616878-7785787
40. Lerman AE, Sadin ML, Trachtman S. Policy uptake as political behavior: evidence from the Affordable Care Act. Am Polit Sci Rev. 2017;111(4):755-770. doi:10.1017/S0003055417000272
41. Durkee A. Trump still wants to kill Obamacare, pandemic be damned. Vanity Fair. May 7, 2020. Accessed June 22, 2020. https://www.vanityfair.com/news/2020/05/trump-still-wants-to-kill-obamacare-coronavirus-aca
42. HHS Secretary Becerra announces reduced costs and expanded access available for Marketplace health coverage under the American Rescue Plan. News release. CMS. April 1, 2021. Accessed July 19, 2021. https://www.cms.gov/newsroom/press-releases/hhs-secretary-becerra-announces-reduced-costs-and-expanded-access-available-marketplace-health
43. Biden-Harris administration launches “Summer Sprint to Coverage” campaign for final 30 days of special enrollment period. News release. CMS. July 15, 2021. Accessed July 19, 2021. https://www.cms.gov/newsroom/press-releases/biden-harris-administration-launches-summer-sprint-coverage-campaign-final-30-days-special