Concentration in Health Insurance Markets
This interactive chart provides details on 1) enrollment in the overall individual market and the individual exchanges as measured by covered life-years, and 2) covered life-years in each state's individual exchange as a proportion of covered life-years in the overall individual market from 2015 through 2022.
Illinois
Source: GAO analysis of data from the Centers for Medicare & Medicaid Services (CMS). | GAO-25-107194
The table below displays data for the selected state. Click here to download the data used in this graphic.
| State | Year | Covered life-years, individual exchange | Covered life-years, individual market | Individual exchange covered life-years as a proportion of overall individual market (%) |
|---|---|---|---|---|
| Illinois | 2015 | 265,422 | 669,502 | 40 |
| Illinois | 2016 | 301,786 | 620,757 | 49 |
| Illinois | 2017 | 278,686 | 489,373 | 57 |
| Illinois | 2018 | 276,179 | 429,326 | 64 |
| Illinois | 2019 | 260,221 | 389,651 | 67 |
| Illinois | 2020 | 257,165 | 373,377 | 69 |
| Illinois | 2021 | 269,542 | 378,798 | 71 |
| Illinois | 2022 | 288,116 | 384,173 | 75 |
- We calculated the size of each market from 2015 through 2022 using covered life-years that issuers reported to Centers for Medicare & Medicaid Services or states. This measure is calculated as the average number of lives insured each month in the reporting year. Rather than a point-in-time measurement, this measure accounts for changes in enrollment that occur throughout the year.
- Covered life-years is one of several ways to measure health insurance enrollment, so it may differ from other measures of market size.
- We rounded market share values of less than 0.5 percent to zero.