Private health insurance is the leading source of health coverage in the United States. Small and large employers may offer fully insured group plans (by purchasing coverage from an issuer) or self-funded group plans (by setting aside funds to pay for employee health care). Most small employers purchase fully insured plans, while most large employers self- fund at least some of their employee health benefits. While the majority of health insurance coverage is provided through the small or large group market, Americans without access to group health coverage, such as those with employers that do not offer health coverage, may choose to purchase it directly from an issuer through the individual market. (See fig. 1 for total covered life-years reported by issuers to CMS in the individual and fully insured small and large group markets.) We previously identified several factors that can affect concentration in health insurance markets. High concentration levels have often been the result of consolidation—mergers and acquisitions—among existing issuers. In addition, concentration can persist because of the difficulty for new issuers to enter the market. For example, new issuers that do not yet have large numbers of enrollees may have greater challenges negotiating discounts with health care providers. PPACA contains provisions that may affect market concentration and competition among health issuers, such as the establishment of health insurance exchanges within each state’s overall individual and small group markets. One goal of the exchanges is for issuers to have an incentive to compete with one another on price and value because consumers can visit a website to compare and select among health plans participating in the exchanges. Issuer participation in the exchanges is a key factor in assuring that consumers have a choice of health plans. While PPACA does not require issuers offering coverage in an overall market to participate in the exchanges, issuers have an incentive to do so in order to access additional consumers. For example, certain consumers earning from 100 to 400 percent of the federal poverty level are eligible to receive premium tax credits that can reduce premium costs, but only for plans purchased through an exchange. The federal government and some states have also instituted other provisions to encourage issuers to participate in the exchanges. For example, PPACA required the establishment of the Consumer Oriented and Operated Plan (CO-OP) program, which provided loans to new consumer-governed, nonprofit issuers that are required to offer health plans in the individual and small group exchanges. In addition, in Maryland, certain issuers that offered plans outside of the exchange are also required to offer plans through the exchange. PPACA also established other key market reforms that apply both within and outside of the exchanges, such as requiring that issuers offer coverage to all individuals regardless of health status and limiting the ability of issuers to deny coverage or charge higher premiums to individuals and small groups based on health risks or certain other factors. Since the enactment of PPACA in 2010, there have been additional federal policy changes that may influence an issuer’s decision about whether to participate in health insurance markets. For example, in 2014, HHS announced that a program that made payments to issuers whose losses exceeded a certain threshold—known as risk corridor payments—would be budget neutral, which resulted in reduced payments for some issuers. One issuer told us that this lower than expected funding was one of multiple factors that contributed to its decision to reduce the number of insurance markets in which it participated. States’ overall individual health insurance markets were generally concentrated in 2015 and 2016, similar to what we reported for previous years. Individual market exchanges—representing 57 percent of the overall individual market nationally in 2016—were also concentrated in most states and in many cases became more concentrated in recent years. States’ overall individual health insurance markets were generally concentrated among a small number of issuers in 2015 and 2016. On average, there were 16 issuers participating in each state in 2016. However, that same year, the 3 largest issuers cumulatively held 80 percent or more of the market—an indicator of high concentration—in 37 of 51 states, generally consistent with what we previously reported for years 2011 through 2014 (see fig. 2). The remaining issuers in each state often had significantly smaller market shares—on average, 12 of the 16 issuers in each state held less than 5 percent market share. We also found that in over half of states in 2016, a single issuer held at least 50 percent of the market, consistent with prior years. Specifically, a single issuer held at least 50 percent market share in 28 states in 2016. Of these states, a single issuer held between 80 and 90 percent market share in 5 states, and more than 90 percent market share in 2 states. For example, although West Virginia had 15 issuers in 2016, a single issuer, Highmark, held 91 percent market share. This largest issuer position was held by the same company in both 2015 and 2016 in 45 states; in 35 of these states, the largest issuer had been the same since 2011. While states’ overall individual markets generally remained concentrated, they experienced fluctuations in the extent of concentration in recent years. Specifically, from 2014—the last year of data on which we previously reported—to 2016, the market share of the three largest issuers increased in 30 states (with a median increase of 4 percentage points) and decreased in 21 states (with a median decrease of 6 percentage points). (See fig. 3.) However, despite these changes, states that were highly concentrated in 2014—that is, where the market share of the three largest issuers was at least 80 percent—generally remained highly concentrated in 2016. Our analyses found that states’ individual market exchanges—collectively representing 57 percent of enrollment in the overall individual market nationally in 2016—were generally concentrated among a small number of issuers from 2015 to 2017. Each year during this time period, for the 49 states for which we had complete data, on average, between 3 and 5 issuers participated in the individual market exchanges across the states’ rating areas. Further, each year, the three largest issuers held 80 percent or more of the exchange market, on average, across the states’ rating areas, in at least 46 states. For example, in Wisconsin in 2017, the market share of the three largest issuers ranged from 75 percent in 2 of the state’s 16 rating areas to 100 percent in 6 rating areas; on average, the three largest issuers held 92 percent market share across the 16 rating areas. While the number of states meeting this 80 percent average threshold for high concentration remained relatively constant from 2015 through 2017, market share was increasingly concentrated among a smaller number of issuers in many states, as fewer issuers participated in the exchanges by 2017. The number of states with three or fewer issuers, on average, in their rating areas—and where the issuers therefore held, on average, 100 percent or nearly 100 percent market share—increased from 16 states in 2015 to 32 states in 2017. (See fig. 4.) Further, we found that in at least 35 states each year from 2015 through 2017, the average market share of the largest individual market exchange issuer across the states’ rating areas was at least 50 percent. For example, although Kansas had up to three participating exchange issuers in each of its rating areas in 2017, the largest issuer in each rating area— generally Blue Cross and Blue Shield of Kansas—had at least 88 percent market share. We also found that many states’ individual market exchanges became more concentrated from 2015 to 2017. In 32 of the 49 states, the average market share of the largest exchange issuer across the states’ rating areas increased between 2015 and 2017, with a median increase of 13 percentage points. (See fig. 5.) For example: In Arizona, the average market share of the largest exchange issuer across the state’s rating areas increased by about 60 percentage points, from 39 percent in 2015 to 98 percent in 2017. This increase corresponded with a decrease in issuer participation in the exchange; the state’s seven rating areas had between 7 and 12 issuers in 2015, but by 2017 had only 1 or 2 issuers. In 2015, a CO-OP, Compass Cooperative Health Plan, Inc., had 29 percent of the total exchange market share statewide in Arizona and was among the largest issuers in three rating areas, but it exited the exchange after that year. Other, smaller issuers also exited the exchange after 2015 and 2016, and, in 2017, Blue Cross Blue Shield of Arizona was left as the only issuer in five of the state’s rating areas. In South Carolina, the average market share of the largest exchange issuer increased by 41 percentage points, from 59 percent in 2015 to 100 percent in 2017. As in Arizona, the increase corresponded with a decrease in issuer participation in the exchange, from 2 to 4 issuers in the state’s 46 rating areas in 2015 to only 1 issuer—BlueCross BlueShield of South Carolina—in each rating area in 2017. In addition, a CO-OP, Consumers’ Choice Health Insurance Company, had 43 percent of the total exchange market share statewide and was the largest issuer in nearly half of the state’s rating areas in 2015, but it exited the exchange after that year. In contrast, BlueCross BlueShield of South Carolina had 42 percent of the total exchange market share statewide and was the largest issuer in about half of the rating areas in 2015, and by 2017 was the only remaining issuer in the state. In the remaining 17 states, the average market share of the largest exchange issuer across the states’ rating areas decreased between 2015 and 2017, with a median decrease of 12 percentage points. For example: In Maine, the average market share of the largest exchange issuer decreased by 39 percentage points, from 81 percent in 2015 to 42 percent in 2017. Maine Community Health Options, a CO-OP, remained the largest issuer in each of the state’s four rating areas during this period. However, the other two issuers in these rating areas captured more market share. For instance, Harvard Pilgrim Health Care Group had 1 percent or less market share in each rating area in 2015, but as much as 32 percent market share in one of the state’s rating areas in 2017. In Delaware—which only had one rating area—the market share of the largest exchange issuer decreased by 37 percentage points, from 92 percent in 2015 to 55 percent in 2017. Although the state had the same two issuers, Aetna Group and Highmark Group, throughout this time period—and Highmark Group was the largest issuer each year— Aetna Group’s market share increased from 8 percent in 2015 to 45 percent in 2017. Our analyses found that the overall small group health insurance market remained concentrated in recent years, similar to our prior report. Small group exchanges often had low enrollment—typically less than 1 percent of the overall small group market—and also remained concentrated in recent years. State small group health insurance markets were concentrated among a small number of issuers in 2015 and 2016. On average, there were 8 issuers participating in each state in 2016. However, in that same year the 3 largest issuers cumulatively held 80 percent or more of the market—an indicator of high concentration—in about three-quarters of states, generally consistent with what we previously reported for years 2011 through 2014 (see fig. 6). The remaining issuers in each state often had significantly smaller market shares—on average, 5 of the 8 issuers in each state held less than 5 percent market share. Further, we found that the largest issuers held 50 percent or more of the market in 30 states in 2016. For example, though Louisiana had 6 issuers in 2016, the largest issuer held 76 percent market share. Overall, a single issuer held between 80 and 90 percent market share in 10 states, and more than 90 percent market share in 1 state. This largest issuer position was held by the same company in both 2015 and 2016 in 46 states; in 40 of these states, the largest issuer had been the same since 2011. While states’ overall small group markets remained concentrated, they experienced fluctuations in concentration in recent years. From 2014 through 2016, the market share of the 3 largest issuers increased in 35 states (with a median increase of 3 percentage points), remained the same in 1 state, and decreased in 15 states (with a median decrease of 1 percentage point). (See fig. 7.) However, despite these changes, states that were highly concentrated in 2014—that is, where the market share of the three largest issuers was at least 80 percent—generally remained highly concentrated in 2016. Our analyses found that states’ SHOP exchanges remained concentrated from 2015 to 2017, with only slight overall changes in issuer participation or market share. Further, as a proportion of the overall small group market, SHOP exchanges in most states had little enrollment. (See sidebar.) Small Group Health Options Program (SHOP) Enrollment as a Proportion of the Overall Small Group Market As a proportion of the overall small group market, SHOP exchanges in most states had little enrollment—that is, typically less than 1 percent of the overall small group market. For example, in 2016, Alaska’s small group market had 17,257 covered life-years, while its SHOP exchange had 96 covered life-years (0.6 percent). The District of Columbia, Rhode Island, and Vermont were the only states where the SHOP exchange was more than 3 percent of the overall small group market. The District of Columbia and Vermont require all small group plans to be purchased through the state’s SHOP exchange. (See app. III.) In each year, more than 31 of the 46 states for which we had data had three or fewer issuers in the SHOP exchange; therefore between one and three issuers held 100 percent of the market share for the state. Among states with four or more issuers, the market share of the three largest issuers was typically at least 80 percent. For example, California had 6 participating issuers from 2015 through 2017 in the SHOP exchange, and the market share for the three largest issuers in that state ranged from 92 to 93 percent across the 3 years. (See fig. 8.) On average, the number of participating issuers in the SHOP exchange decreased slightly from 2015 through 2017. However, in a few states, there were larger changes in issuer participation and concentration. For example, Ohio’s SHOP exchange had 7 participating issuers in 2015, decreasing to 4 issuers in 2017. Across this time period, the market share of the three largest issuers in Ohio’s SHOP exchange increased from 59 percent to 98 percent. Conversely, New York’s SHOP exchange had 10 issuers in 2015, decreasing to 8 issuers in 2017; but the market share of the three largest issuers decreased by almost 7 percentage points within that time. Further, we found that in at least 38 of 46 states each year from 2015 through 2017, the largest issuer held at least 50 percent of the SHOP exchange market share. In 23 states, the market share of the largest issuer increased during this period, with a median increase of 11 percentage points, and in 6 additional states the largest issuer was the only issuer in the SHOP exchange and thus held 100 percent market share for all 3 years. (See fig. 9.) For example: In Kentucky, the market share of the largest issuer in the SHOP exchange increased by 56 percentage points, from 42 percent in 2015 to 98 percent in 2017. In 2015, the largest issuer was Kentucky Health Cooperative, a CO-OP that exited the SHOP exchange after 2016. The second largest issuer in 2015, Wellpoint Inc. Group, increased market share over this time period, from 33 percent in 2015 to 98 percent in 2017, becoming the largest issuer. The market share of the other remaining issuer in Kentucky’s SHOP exchange, Baptist Health Plan, Inc., decreased from 19 percent in 2015 to 1 percent in 2017. In Ohio, the market share of the largest issuer in the SHOP exchange increased by 54 percentage points, from 29 percent in 2015 to 83 percent in 2017. Across this time period, the largest issuer changed from Medical Mutual of Ohio (which had 29 percent market share in 2015 and 8 percent in 2017) to Wellpoint Inc. Group (which had 12 percent market share in 2015 and 83 percent in 2017). This increase in the largest issuer’s market share corresponded with a decrease in issuer participation. The state had 7 participating issuers in 2015, decreasing to 4 in 2017. The market share of the 3 issuers that left ranged from 9 to 16 percent. In the remaining 17 states, the market share of the largest issuer decreased between 2015 and 2017, with a median decrease of 7 percentage points. In some states, these decreases were significant. For example, in Maine, the market share of the largest issuer, Maine Community Health Options—a CO-OP—decreased by 40 percentage points, from 89 percent in 2015 to 49 percent in 2017. During this time period, while Maine Community Health Options remained the largest issuer, the other two participating issuers gained additional market share. For example, Harvard Pilgrim Health Care Group increased market share from 6 percent in 2015 to 38 percent in 2017. In 2015 and 2016, states’ overall large group health insurance markets remained concentrated, as in prior years. On average, there were 10 participating issuers in each state in 2016. However, in that same year the 3 largest issuers held at least 80 percent market share in 43 of 51 states, which is generally consistent with prior years. (See fig. 10.) In 2016, 3 issuers held 99 or 100 percent of the large group market in 7 states—Alabama, Alaska, Mississippi, Nebraska, North Dakota, South Carolina, and Vermont. The remaining issuers in each state often had significantly smaller market shares—on average, 6 of the 10 participating issuers in each state held less than 5 percent market share. In more than 30 states in 2015 and 2016, market share was not only concentrated among a small number of issuers, but a single issuer held at least 50 percent of the overall large group market, as in prior years. A single issuer held at least 50 percent market share in 33 states in 2016, with significantly higher levels of concentration by the largest issuer in some states. For example, in 2016, a single issuer held at least 90 percent of the market in Alabama and at least 80 percent of the market in 5 other states (Alaska, Mississippi, Montana, South Carolina, and Vermont). Further, this largest issuer position was held by the same company in 2015 and 2016 in 49 states; and, in 47 of those states, the largest issuer position has been held by the same company since 2011. The extent of concentration in the overall large group market remained relatively constant when comparing 2014—the last year of data on which we previously reported—to 2016. The market share of the 3 largest issuers increased in 24 states and decreased in 24. (See fig. 11.) The largest increase was in Wisconsin, where the market share of the 3 largest issuers increased from 38 percent in 2014 to 44 percent in 2016, and the largest decrease was in New York, where the market share of the 3 largest issuers decreased from 55 percent in 2014 to 47 percent in 2016. We provided a draft of this report to HHS for review and comment. The department provided technical comments, which we incorporated as appropriate. We are sending copies of this report to the appropriate Congressional committees, the Secretary of Health and Human Services, and other interested parties. In addition, the report is available at no charge on the GAO website at http://www.gao.gov. If you or your staff have any questions about this report, please contact me at (202) 512-7114 or dickenj@gao.gov. Contact points for our Offices of Congressional Relations and Public Affairs may be found on the last page of this report. GAO staff who made key contributions to this report are listed in appendix IX. This table presents covered life-years in each state’s individual market health insurance exchange as a proportion of total covered life-years in each state’s overall individual market in 2016. The four tables below present information on the number of participating issuers and market share of the largest issuers in each state’s individual market exchange from 2015 through 2017. Specifically, Table 2 presents the total number of exchange issuers in each state. Table 3 presents the average number of exchange issuers across each state’s rating areas. Table 4 presents the names and market shares of the single largest exchange issuer, and market share of the largest three issuers, for each state. Table 5 presents the average market share of the largest issuer across each state’s rating areas. This table presents covered life-years in each state’s Small Business Health Options Program (SHOP) exchange as a proportion of total covered life-years in each state’s overall small group market in 2016. The two tables below present information on the participation of issuers in each state’s small group health insurance exchange from 2015 to 2017 and the market share of the largest and three largest issuers from 2015 to 2017. The two tables below present information on the participation of issuers in each state’s overall individual health insurance market from 2011 to 2016, and the market share of the largest and three largest issuers from 2014 to 2016. Table 11 provides market share for the 23 consumer operated and oriented plans (CO-OPs) participating in state individual market and Small Business Health Options Program exchanges for 2015 through 2017. CO- OPs are new consumer-governed, nonprofit issuers created under the Patient Protection and Affordable Care Act. Out of the 23 CO-OPs originally operating in 2014, all but four, operating in five states, had ceased operations by the end of 2017. The two tables below present information on the participation of issuers in each state’s overall small group health insurance market from 2011 to 2016 and the market share of the largest and three largest issuers from 2014 to 2016. The two tables below present information on the participation of issuers in each state’s overall large group health insurance market from 2011 to 2016 and the market share of the single largest and three largest issuers from 2014 to 2016. In addition to the contact named above, William D. Hadley, Assistant Director; Katherine L. Amoroso, Analyst-in-Charge; Priyanka Sethi Bansal; Giselle Hicks; John Lalomio; and Sarah-Lynn McGrath made key contributions to this report. Also contributing were Yesook Merrill; Laurie Pachter; Vikki Porter; Oliver Richard; and Emily Wilson.

Summary: A highly concentrated health insurance market may indicate less competition and could affect consumers' choice of issuers and the premiums they pay. In 2014, PPACA required the establishment of health insurance exchanges—a new type of marketplace where individuals and small groups can compare and select among insurance plans sold by participating issuers—and the introduction of other reforms that could affect market concentration and competition among issuers. GAO previously reported that enrollment through these newly established exchanges was also generally concentrated. PPACA included a provision for GAO to study market concentration. This report describes changes in the concentration of enrollment among issuers in (1) overall individual, small group, and large group markets, and (2) individual and small group exchanges. GAO determined market share in the overall markets using enrollment data from 2015 and 2016 that issuers are required to report annually to the Centers for Medicare & Medicaid Services (CMS) and compared that data to 2011 through 2014 enrollment data GAO analyzed in previous reports. GAO determined market share in the exchanges from 2015 through 2017 using other sources of enrollment data from CMS and states. For all data sets, GAO used the most recent data available. Enrollment in private health insurance plans continued to be concentrated among a small number of issuers in 2015 and 2016. In the overall large group market (coverage offered by large employers), small group market (coverage offered by small employers), and individual market (coverage sold directly to individuals), the three largest issuers held 80 percent of the market or more in at least 37 of 51 states. This is similar to what GAO previously reported for 2011 through 2014. GAO also found that within the overall individual and small group markets in each state, the health insurance exchanges established by the Patient Protection and Affordable Care Act (PPACA) were also concentrated from 2015 to 2017. For the individual market exchanges, in each year, three or fewer issuers held 80 percent or more of the market, on average, in at least 46 of the 49 state exchanges for which GAO had data. Further, the largest issuers increased their market share in about two-thirds of exchanges. The number of issuers participating in a market and their market shares can affect concentration, and many individual exchanges generally had a decreasing number of participating issuers over time. For the small group market exchanges, in each year, three or fewer issuers held 80 percent or more of the market in at least 42 of the 46 state exchanges for which GAO had data. The small group exchanges also had slight changes in issuer participation and market share over this time period. GAO received technical comments on a draft of this report from the Department of Health and Human Services and incorporated them as appropriate.