Worst changes in enrollment, based on CMS billable month data. (We divided the billable month figures by 12.) To see more ACA exchange enrollment data cards, click on the arrow on the right side of the gallery box above. It's official: The market for individual major medical coverage that complies fully with the Affordable Care Act went through an economic car wash in 2017. Total enrollment fell about 11%, and the typical monthly premium that an issuer charged increased about 21%. The Centers for Medicare and Medicaid Services has told the story in a new batch of data.

The data

CMS prepares the individual major medical data every year, to run the ACA risk-adjustment program. The program uses cash from issuers that end up with low-risk enrollees to compensate issuers that end up with more than their fair share of the high-risk enrollees. Annual CMS spreadsheets give each state's average monthly premium, and each state's total "billable months." (A user can convert the billable month total into an annual enrollment figure by dividing that number by 12.) CMS has published comparable risk-adjustment data for both 2016 and 2017 for the District of Columbia, and for all states but Hawaii, Massachusetts and Vermont. CMS has actually published 2017 data for Hawaii, although comparable data was missing in the 2016 spreadsheet: Hawaii had average monthly premiums of $477 in 2017, and annualized individual major medical enrollment of about 33,000. The premium figures represent the full amounts that the issuers actually charge. The figures do not include the effects of any ACA premium  tax credit subsidies or other subsidies that might have cut the enrollees' out-of-pocket premium spending. The version of the spreadsheet on the CMS website gives data produced by the federal government. Because the federal government produced the data, and posted it on a public website, agents, insurers and others can use the data in their own reports, articles and social media posts without worries about copyright restrictions.

What CMS found

CMS found that:

• Total individual major medical enrollment in the jurisdictions included fell 11%, to about 12.7 million.
• The enrollment decrease ranged from a drop of 37%, in one state, to an increase of 2%, in Arkansas and Delaware.
• The typical state's average monthly premium increased 21%. Half had increases about the size or lower, and half had increases about that size or lower.
• The average premium change ranged from a low of close to zero, in North Dakota, to a high of 99%, in Arizona.
• The median statewide average monthly premium was $466.
• State's statewide average monthly premiums ranged from $336 in Utah, to $1,048, in Alaska.

We posted a collection of data cards above that show the states with the five most dramatic drops in individual major medical enrollment. Look below for a table showing what happened in all of the jurisdictions included in both the 2016 and 2017 spring risk-adjustment market data spreadsheets.

Non-Grandfathered Individual Major Medical Coverage:  Premiums and Enrollment
	2018		2017
	AVERAGE MONTHLY PREMIUMS	ANNUALIZED ENROLLMENT	AVERAGE MONTHLY PREMIUMS	ANNUALIZED ENROLLMENT	CHANGE IN PREMIUMS	CHANGE IN ENROLLMENT
Alabama	$574	189,575	$415	204,804	38%	-7%
Alaska	$1,048	15,863	$869	17,519	21%	-9%
Arizona	$630	146,505	$317	233,036	99%	-37%
Arkansas	$390	337,510	$369	332,251	6%	2%
California	$440	2,072,021	$398	2,131,989	11%	-3%
Colorado	$439	228,489	$375	264,328	17%	-14%
Connecticut	$537	143,218	$439	171,183	22%	-16%
Delaware	$366	16,815	$324	16,411	13%	2%
District of Columbia	$573	26,019	$472	34,446	21%	-24%
Florida	$461	1,533,948	$402	1,594,269	15%	-4%
Georgia	$443	483,761	$381	568,381	16%	-15%
Idaho	$432	98,329	$355	114,345	22%	-14%
Illinois	$522	381,227	$368	493,915	42%	-23%
Indiana	$432	165,909	$409	200,993	6%	-17%
Iowa	$541	55,505	$406	80,497	33%	-31%
Kansas	$466	110,139	$342	130,293	36%	-15%
Kentucky	$406	92,840	$357	104,091	14%	-11%
Louisiana	$560	133,212	$447	208,761	25%	-36%
Maine	$520	75,631	$412	81,088	26%	-7%
Maryland	$435	214,474	$335	247,279	30%	-13%
Michigan	$410	358,046	$389	398,972	6%	-10%
Minnesota	$557	149,216	$386	228,650	44%	-35%
Mississippi	$466	80,687	$401	90,289	16%	-11%
Missouri	$480	233,244	$398	285,697	21%	-18%
Montana	$581	55,609	$396	72,372	47%	-23%
Nebraska	$619	74,427	$401	104,367	55%	-29%
Nevada	$382	113,009	$356	127,965	7%	-12%
New Hampshire	$412	96,060	$364	95,086	13%	1%
New Jersey	$492	338,702	$484	335,892	2%	1%
New Mexico	$385	64,823	$318	71,737	21%	-10%
New York	$525	306,037	$475	326,260	11%	-6%
North Carolina	$676	474,978	$501	528,849	35%	-10%
North Dakota	$429	38,731	$427	39,377	0%	-2%
Ohio	$422	247,116	$399	270,735	6%	-9%
Oklahoma	$620	128,952	$358	168,400	73%	-23%
Oregon	$446	205,553	$356	221,051	25%	-7%
Pennsylvania	$518	489,991	$380	566,746	36%	-14%
Rhode Island	$383	42,973	$377	45,419	2%	-5%
South Carolina	$521	200,171	$409	215,517	27%	-7%
South Dakota	$529	35,053	$398	38,140	33%	-8%
Tennessee	$579	225,240	$389	295,415	49%	-24%
Texas	$421	1,037,404	$347	1,241,699	21%	-16%
Utah	$336	181,649	$284	192,578	18%	-6%
Virginia	$413	399,108	$364	426,925	13%	-7%
Washington	$404	279,732	$373	310,998	8%	-10%
West Virginia	$694	33,346	$513	43,316	35%	-23%
Wisconsin	$528	226,558	$455	243,033	16%	-7%
Wyoming	$620	26,029	$574	25,828	8%	1%
AVERAGE	$501	263,822	$406	296,691	24%	-11%
Source: Census Bureau

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