Health Insurance: Uninsured by State, 2005-2007

Health Insurance: Uninsured
by State, 2005-2007
Chris L. Peterson and April Grady
Domestic Social Policy Division
Summary
Based on data from the Census Bureau’s Current Population Survey (CPS), an
estimated 45.7 million people lacked health insurance coverage in 2007, representing

15.3% of the civilian noninstitutionalized U.S. population.


When comparing state-level health insurance estimates, a three-year average is used
to increase their reliability. During 2005-2007, the estimated average percentage
uninsured was 15.5% nationally, ranging from a low of 8.3% in Massachusetts to a high
of 24.5% in Texas. States in the Midwest and Northeast generally had lower uninsured
rates than those in the South and West.
These state-level estimates must be interpreted with caution because they are based
on a sample of the population. When sampling variation is taken into account, the
uninsured rate in nine states is not statistically different from the national rate. The
uninsured rate in 28 states and the District of Columbia is statistically lower than the
national rate, and statistically higher in the remaining 13 states.
Estimates of Health Insurance Coverage, by State
During 2005-2007, the estimated average percentage uninsured was 15.5%
nationally. Table 1 shows that 2005-2007 average uninsured rates ranged from 8.3% in
Massachusetts to 24.5% in Texas. Eight states (Massachusetts, Hawaii, Minnesota,
Wisconsin, Iowa, Maine, Pennsylvania, and Connecticut) had three-year average
uninsured rates of less than 10.0%. Three states (Florida, New Mexico, and Texas) had
average uninsured rates of 20.0% or more. Generally, states with the lowest uninsured
rates were located in the Midwest and Northeast; states with the highest rates were in the
South and West (Figure 1).



Table 1 provides private health insurance,1 public health insurance,2 and uninsured
estimates with percentage rankings by state. The right side of the table indicates whether
a state’s three-year average uninsured rate is statistically lower (shown with a “-”),
statistically higher (shown with a “+”), or not statistically different (shown with a “x”)3
than the national rate of 15.5%.
Both private and public health insurance affect a state’s uninsured rate. For example,
as shown in Table 1, Minnesota and Maine have similarly low uninsured rates.4
However, Minnesota has the highest three-year average private coverage rate in the
country (79.7%) and a relatively low public coverage rate (24.0%). On the other hand,
Maine has a lower three-year average private coverage rate (69.5%) and the highest public
coverage rate (35.9%). Thus, even though there are differences regarding whether people
in Maine and Minnesota obtain private or public health insurance, the impact is that both
have similarly low uninsured rates.
States with the highest rankings for average percentage uninsured during 2005-2007,
led by Texas with nearly a quarter of its population, have some of the lowest rankings for
private coverage. All but two of the 10 states with the highest uninsured rates (shown in
the last 10 rows of Table 1) rank in the lowest 10 states for private coverage.
Estimates with 95% Confidence Intervals. The estimates in this report are
based on data from the March 2008 supplement to the Current Population Survey (CPS).5
The CPS is representative of the civilian noninstitutionalized population and is designed
to produce reliable estimates at the national, regional, and state levels.
The small sample sizes available from the CPS for many states make it prudent to
use a three-year average when comparing state-level estimates and to consider the
estimates in terms of a range of values. Like Table 1, Table 2 shows the best point
estimates, or single values, for the average number and percentage of people covered and
not covered by health insurance. It also reports a range of values — the 95% confidence
interval — for these estimates. The larger the confidence interval in relation to the size
of the estimate, the less reliable the estimate. The size of the range depends primarily on
the sample size. A 95% confidence interval means that if repeated samples were collected
under essentially the same conditions and their confidence intervals calculated, in the long


1 Coverage through an employer or union, all coverage from outside the home, and coverage
purchased directly from a private insurer.
2 Medicare, Medicaid, the State Children’s Health Insurance Program (SCHIP), and other
government-provided health insurance, as well as coverage related to employment in the military.
3 Statistical significance was tested at the 95% confidence level (also referred to as the 5%
significance level). This means that one can be 95% certain that the difference between a state’s
uninsured rate and the national rate is not zero (i.e., the state’s rate is statistically higher or lower)
or could be zero (i.e., the state’s rate is not statistically different).
4 Their uninsured rates are statistically lower than the national rate and are not statistically
different from each other.
5 Because the supplement is now fielded from February through April, it has been officially
renamed the Annual Social and Economic supplement (ASEC) to the CPS, though many analysts
continue to refer to it by its traditional name.

run about 95% of those intervals would contain the true number of people with (or
without) health insurance.
Reasons for Differences in the Percentage Uninsured
Figure 1 indicates that people in the South and West are more likely to lack health
insurance, and that residents of the Midwest and Northeast are more likely to be covered.
Various characteristics of a state’s population may account for these differences.
Nationwide, the uninsured rate is related to age, race and ethnicity, employment, and a6
number of other factors. The prevalence of particular population and employer
characteristics may account for some of the regional or state variation in uninsured rates.
The percentage of a state’s population that is uninsured may also be affected by state
policies, such as eligibility criteria for the state’s Medicaid program or its State Children’s
Health Insurance Program (SCHIP).


6 For more information, see CRS Report 96-891, Health Insurance Coverage: Characteristics
of the Insured and Uninsured Populations in 2007, by Chris L. Peterson and April Grady.

Table 1. Health Insurance Coverage Estimates with Rankings, by State,
2005-2007 Average
(sorted by percentage uninsured ranking, numbers in thousands)
Public health insurance
Private health insurance(including military)Uninsured
P ercent P ercent P ercent
StateTotal populationNumberNumberNumberValueRankValueRankValueRank
United States296,588201,61668.0%NA81,17127.4%NA45,82215.5%NANA
Massachusetts 6,334 4,731 74.7% 9 1 ,768 27.9% 25 527 8.3% - 1
Hawaii 1,267 945 74.6% 12 404 31.9% 10 105 8.3% - 2
Minneso ta 5,156 4,110 79.7% 1 1 ,238 24.0% 45 438 8.5% - 3
Wisconsin 5,465 4,218 77.2% 5 1 ,413 25.9% 36 480 8.8% - 4
Io wa 2,933 2,290 78.1% 3 778 26.5% 35 274 9.4% - 5
Maine 1 ,316 915 69.5% 29 472 35.9% 1 125 9.5% - 6
P ennsylvania 12,313 9,356 76.0% 7 3 ,380 27.5% 29 1,203 9.8% - 7
Connecticut 3,475 2,657 76.4% 6 892 25.7% 38 344 9.9% - 8
Rhode Island1,05176172.4%2132130.6%1510810.3%-9
New Hampshire1,3081,04079.5%227921.4%4813810.5%-10
Mich igan 9,960 7,418 74.5% 13 2,738 27.5% 28 1,075 10.8% - 1 1
Vermont 619 435 70.4% 28 204 33.0% 5 68 11.0% - 12
Oh io 11,318 8,307 73.4% 15 3,076 27.2% 31 1,249 11.0% - 1 3
North Dakota61948277.9%415224.5%426811.1%-14
South Dakota77657974.6%1122128.5%228711.2%-15
District of Columbia56437366.2%3618032.0%86411.4%-16
Kansas 2,713 2,026 74.7% 10 739 27.3% 30 320 11.8% - 1 7
Delaware 856 625 73.0% 19 239 27.9% 26 101 11.8% - 1 8
Nebraska 1,762 1,326 75.2% 8 438 24.8% 41 212 12.0% - 1 9
Wash ington 6,359 4,604 72.4% 22 1,796 28.2% 23 770 12.1% - 2 0
Indian a 6 ,247 4,584 73.4% 16 1,522 24.4% 43 766 12.3% - 2 1
Missouri 5 ,767 4,093 71.0% 26 1,617 28.0% 24 723 12.5% - 2 2
New York19,04112,64966.4%355,89330.9%132,55113.4%-23
Virginia 7,559 5,414 71.6% 24 2,091 27.7% 27 1,031 13.6% - 2 4
Maryland 5,582 4,158 74.5% 14 1,339 24.0% 46 761 13.6% - 2 5
Illinois 12,647 9,182 72.6% 20 3,056 24.2% 44 1,735 13.7% - 2 6
Kentucky 4,122 2,750 66.7% 34 1,282 31.1% 11 569 13.8% - 2 7
Tennessee 5 ,979 3,859 64.5% 40 1,985 33.2% 4 830 13.9% - 2 8
Alab ama 4 ,542 3,113 68.5% 32 1,391 30.6% 14 632 13.9% - 2 9
Wyoming 515 370 71.9% 23 139 27.0% 32 73 14.3% x 3 0
Id ah o 1 ,473 1,039 70.5% 27 375 25.5% 39 216 14.7% x 3 1
West Virginia1,8031,15564.1%4162334.6%226814.8%x32
New Jersey8,6476,33773.3%171,78520.6%491,31815.2%x33
Utah 2,573 1,880 73.1% 18 510 19.8% 51 399 15.5% x 3 4
Montan a 933 631 67.7% 33 273 29.3% 20 150 16.1% x 3 5
South Carolina4,2642,75964.7%391,27830.0%1770516.5%x36
North Carolina8,8655,77665.2%372,60329.4%191,46916.6%+37
Co lorado 4,773 3,406 71.3% 25 980 20.5% 50 799 16.7% x 3 8
Oregon 3,702 2,554 69.0% 30 953 25.7% 37 621 16.8% x 3 9
Alaska 664 421 63.3% 42 206 31.1% 12 115 17.3% + 4 0
Arkansas 2,774 1,699 61.2% 46 888 32.0% 9 485 17.5% + 4 1
Georgia 9 ,295 6,031 64.9% 38 2,469 26.6% 34 1,658 17.8% + 4 2
Nevada 2,517 1,726 68.6% 31 549 21.8% 47 452 18.0% + 4 3
Oklahoma 3 ,516 2,177 61.9% 45 1,131 32.2% 7 640 18.2% + 4 4
California 36,148 22,650 62.7% 44 9,651 26.7% 33 6,720 18.6% + 4 5
Mississippi 2,883 1,660 57.6% 50 971 33.7% 3 543 18.8% + 4 6
Louisian a 4 ,166 2,538 60.9% 47 1,240 29.8% 18 807 19.4% + 4 7
Arizona 6,228 3,768 60.5% 48 1,876 30.1% 16 1,219 19.6% + 4 8
Florida 18,007 11,355 63.1% 43 5,216 29.0% 21 3,698 20.5% + 4 9
New Mexico1,9431,09556.4%5163732.8%642521.9%+50
Texas 23,253 13,590 58.4% 49 5,911 25.4% 40 5,687 24.5% + 5 1
Source: CRS analysis of data from the March 2008 Current Population Survey (CPS).
Notes: People may have both private and public coverage. On the right side of the table, “-” indicates that a state’s uninsured rate
is statistically lower than the national rate, “+” indicates that it is statistically higher, andx” indicates that it is not statistically
different. Statistical significance was tested at the 95% confidence level (see text for more information).



Table 2. Health Insurance Coverage Estimates with 95% Confidence Intervals,
by State, 2005-2007 Average
(numbers in thousands)
Public health insurance
Private health insurance(including military)Uninsured
State Number P ercent N umber P ercent N umber P ercent
United States201,616+/-50968.0%+/-0.2%81,171+/-52927.4%+/-0.2%45,822+/-42915.5%+/-0.1%
Alab ama 3 ,113 +/- 6 5 68.5% +/- 1 .5% 1 ,391 +/- 6 9 30.6% +/- 1 .5% 632 +/- 5 2 13.9% +/- 1 .1%
Alaska 421 +/- 1 0 63.3% +/- 1 .7% 206 +/- 1 1 31.1% +/- 1 .7% 115 +/- 9 17.3% +/- 1 .4%
Arizona 3,768 +/- 8 6 60.5% +/- 1 .5% 1 ,876 +/- 8 7 30.1% +/- 1 .4% 1 ,219 +/- 7 6 19.6% +/- 1 .2%
Arkansas 1,699 +/- 4 3 61.2% +/- 1 .7% 888 +/- 4 4 32.0% +/- 1 .6% 485 +/- 3 6 17.5% +/- 1 .3%
California 22,650 +/- 207 62.7% +/- 0 .6% 9 ,651 +/- 205 26.7% +/- 0 .6% 6 ,720 +/- 180 18.6% +/- 0 .5%
Co lorado 3,406 +/- 6 8 71.3% +/- 1 .6% 980 +/- 6 7 20.5% +/- 1 .4% 799 +/- 6 1 16.7% +/- 1 .3%
Connecticut 2,657 +/- 4 7 76.4% +/- 1 .5% 892 +/- 5 3 25.7% +/- 1 .5% 344 +/- 3 6 9 .9% +/- 1.0%
Delaware 625 +/- 1 2 73.0% +/- 1 .6% 239 +/- 1 3 27.9% +/- 1 .6% 101 +/- 1 0 11.8% +/- 1 .1%
District of Columbia373+/-1066.2%+/-1.8%180+/-1032.0%+/-1.8%64+/-711.4%+/-1.2%
Florida 11,355 +/- 138 63.1% +/- 0 .8% 5 ,216 +/- 140 29.0% +/- 0 .8% 3 ,698 +/- 125 20.5% +/- 0 .7%
Georgia 6 ,031 +/- 9 6 64.9% +/- 1 .1% 2 ,469 +/- 9 6 26.6% +/- 1 .0% 1 ,658 +/- 8 4 17.8% +/- 0 .9%
Hawaii 945 +/- 1 7 74.6% +/- 1 .4% 404 +/- 1 9 31.9% +/- 1 .5% 105 +/- 1 2 8 .3% +/- 0.9%
Id ah o 1 ,039 +/- 2 1 70.5% +/- 1 .6% 375 +/- 2 2 25.5% +/- 1 .5% 216 +/- 1 8 14.7% +/- 1 .2%
Illinois 9 ,182 +/- 108 72.6% +/- 0 .9% 3 ,056 +/- 112 24.2% +/- 0 .9% 1 ,735 +/- 9 0 13.7% +/- 0 .7%
Indian a 4 ,584 +/- 7 3 73.4% +/- 1 .3% 1 ,522 +/- 7 7 24.4% +/- 1 .2% 766 +/- 5 9 12.3% +/- 0 .9%
Io wa 2,290 +/- 4 0 78.1% +/- 1 .5% 778 +/- 4 6 26.5% +/- 1 .6% 274 +/- 3 0 9 .4% +/- 1.0%
Kansas 2,026 +/- 3 9 74.7% +/- 1 .5% 739 +/- 4 3 27.3% +/- 1 .6% 320 +/- 3 1 11.8% +/- 1 .1%
Kentucky 2,750 +/- 6 3 66.7% +/- 1 .6% 1 ,282 +/- 6 6 31.1% +/- 1 .6% 569 +/- 4 9 13.8% +/- 1 .2%
Louisian a 2 ,538 +/- 6 5 60.9% +/- 1 .7% 1 ,240 +/- 6 6 29.8% +/- 1 .6% 807 +/- 5 7 19.4% +/- 1 .4%
Maine 915 +/- 2 1 69.5% +/- 1 .7% 472 +/- 2 4 35.9% +/- 1 .8% 125 +/- 1 4 9 .5% +/- 1.1%
Maryland 4,158 +/- 6 9 74.5% +/- 1 .4% 1 ,339 +/- 7 4 24.0% +/- 1 .3% 761 +/- 5 9 13.6% +/- 1 .1%
Massachusetts 4,731 +/- 7 2 74.7% +/- 1 .2% 1 ,768 +/- 8 0 27.9% +/- 1 .3% 527 +/- 4 9 8 .3% +/- 0.8%
Mich igan 7,418 +/- 9 2 74.5% +/- 1 .0% 2 ,738 +/- 101 27.5% +/- 1 .0% 1 ,075 +/- 7 0 10.8% +/- 0 .7%
Minneso ta 4,110 +/- 5 9 79.7% +/- 1 .3% 1 ,238 +/- 6 9 24.0% +/- 1 .3% 438 +/- 4 5 8 .5% +/- 0.9%
Mississippi 1,660 +/- 4 5 57.6% +/- 1 .7% 971 +/- 4 6 33.7% +/- 1 .6% 543 +/- 3 8 18.8% +/- 1 .3%
Missouri 4 ,093 +/- 7 3 71.0% +/- 1 .4% 1 ,617 +/- 7 8 28.0% +/- 1 .4% 723 +/- 5 8 12.5% +/- 1 .0%
Montan a 631 +/- 1 4 67.7% +/- 1 .6% 273 +/- 1 5 29.3% +/- 1 .6% 150 +/- 1 2 16.1% +/- 1 .3%
Nebraska 1,326 +/- 2 4 75.2% +/- 1 .5% 438 +/- 2 7 24.8% +/- 1 .5% 212 +/- 2 0 12.0% +/- 1 .1%
Nevada 1,726 +/- 3 8 68.6% +/- 1 .7% 549 +/- 3 7 21.8% +/- 1 .5% 452 +/- 3 4 18.0% +/- 1 .4%
New Hampshire1,040+/-1779.5%+/-1.4%279+/-1921.4%+/-1.4%138+/-1410.5%+/-1.1%
New Jersey6,337+/-8773.3%+/-1.1%1,785+/-8720.6%+/-1.0%1,318+/-7715.2%+/-0.9%
New Mexico1,095+/-3456.4%+/-1.9%637+/-3432.8%+/-1.8%425+/-3021.9%+/-1.6%
New York12,649+/-14266.4%+/-0.8%5,893+/-15030.9%+/-0.8%2,551+/-11113.4%+/-0.6%
North Carolina5,776+/-9465.2%+/-1.2%2,603+/-9829.4%+/-1.1%1,469+/-8016.6%+/-0.9%
North Dakota482+/-877.9%+/-1.5%152+/-924.5%+/-1.5%68+/-711.1%+/-1.1%
Oh io 8,307 +/- 9 9 73.4% +/- 0 .9% 3 ,076 +/- 108 27.2% +/- 1 .0% 1 ,249 +/- 7 6 11.0% +/- 0 .7%
Oklahoma 2 ,177 +/- 5 5 61.9% +/- 1 .7% 1 ,131 +/- 5 8 32.2% +/- 1 .6% 640 +/- 4 8 18.2% +/- 1 .4%
Oregon 2,554 +/- 5 7 69.0% +/- 1 .7% 953 +/- 5 8 25.7% +/- 1 .6% 621 +/- 5 0 16.8% +/- 1 .3%
P ennsylvania 9 ,356 +/- 9 9 76.0% +/- 0 .9% 3 ,380 +/- 113 27.5% +/- 0 .9% 1 ,203 +/- 7 5 9 .8% +/- 0.6%
Rhode Island761+/-1672.4%+/-1.6%321+/-1830.6%+/-1.7%108+/-1210.3%+/-1.1%
South Carolina2,759+/-6564.7%+/-1.6%1,278+/-6730.0%+/-1.6%705+/-5416.5%+/-1.3%
South Dakota579+/-1074.6%+/-1.4%221+/-1128.5%+/-1.5%87+/-811.2%+/-1.0%
Tennessee 3 ,859 +/- 7 8 64.5% +/- 1 .4% 1 ,985 +/- 8 3 33.2% +/- 1 .4% 830 +/- 6 1 13.9% +/- 1 .0%
Texas 13,590 +/- 172 58.4% +/- 0 .8% 5 ,911 +/- 164 25.4% +/- 0 .7% 5 ,687 +/- 161 24.5% +/- 0 .7%
Utah 1,880 +/- 3 3 73.1% +/- 1 .4% 510 +/- 3 2 19.8% +/- 1 .3% 399 +/- 2 9 15.5% +/- 1 .1%
Vermont 435 +/- 1 0 70.4% +/- 1 .7% 204 +/- 1 1 33.0% +/- 1 .7% 6 8 +/- 7 11.0% +/- 1 .2%
Virginia 5,414 +/- 8 1 71.6% +/- 1 .2% 2 ,091 +/- 8 8 27.7% +/- 1 .2% 1 ,031 +/- 6 7 13.6% +/- 0 .9%
Wash ington 4,604 +/- 7 7 72.4% +/- 1 .3% 1 ,796 +/- 8 4 28.2% +/- 1 .3% 770 +/- 6 1 12.1% +/- 1 .0%
West Virginia1,155+/-2664.1%+/-1.5%623+/-2734.6%+/-1.5%268+/-2114.8%+/-1.1%
Wisconsin 4,218 +/- 6 6 77.2% +/- 1 .3% 1 ,413 +/- 7 4 25.9% +/- 1 .4% 480 +/- 4 8 8 .8% +/- 0.9%
Wyoming 370 +/- 8 71.9% +/- 1 .7% 139 +/- 8 27.0% +/- 1 .7% 7 3 +/- 7 14.3% +/- 1 .3%
Source: CRS analysis of data from the March 2008 Current Population Survey (CPS).
Notes: People may have both private and public coverage. The 95% confidence interval is a measure of an estimate’s variability
(see text for more information).



Figure 1. Percentage Uninsured, by State, 2005-2007 Average


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CRS analysis of data from the March 2008 Current Population Survey (CPS).
States in the 14.3%-16.8% category are not statistically different from the national rate, except for North Carolina (which is statistically higher). Others are statistically higher
han 16.8% category) or lower (less than 14.3% category)