Medicare Around the Country

PERC’s Medicare Maps have been updated this year using data from the Centers for Medicare and Medicaid Services (CMS) Medicare Geographic Variation data. The maps allow you to compare average Medicare spending under Parts A and B per enrollee, Medicare enrollment, Medicare Advantage enrollment, average risk scores, and Medicaid eligibility rates at the county and state levels. The maps and underlying data are available for the years 2007 to 2017. We adopted a new data source for this year’s update of the Medicare maps. The previous versions of PERC’s Medicare maps used the CMS’s Medicare Advantage Rates and Statistics data.

The interactive dashboard below depicts the counties by quintiles based on average Medicare spending under Parts A and B per fee-for-service enrollee in 2017. The scatter plot displays the counties and their percentile locations in 2007 and their percentile location in 2017. Together, these two figures show how spending in each county changed over time and they summarize the average spending series on the Medicare Map. The dashboard can be used to select individual counties or groups of counties in the map and the corresponding counties are highlighted in the scatter plot. You can also select counties that were in the same quintiles in both years by selecting an area in the scatter plot.
Medicare Maps
Below we summarize the data underlying PERC’s Medicare Maps.
Average Medicare Spending
The table below reflects actual average Part A and B spending for both aged and disabled beneficiaries and are based on fee-for-service spending (the averages do not include beneficiaries who participate in Medicare Advantage plans). Part D spending (pharmaceuticals) is not included in the average. The averages are from 2017 and are adjusted to 2018 dollars using the personal consumption expenditures price deflator. The population on which the average was calculated is restricted to beneficiaries who were not enrolled in a Medicare Advantage plan during the year and who were enrolled in Part A and Part B for the entire year.
The top panel in the table presents the ten counties with the highest spending per fee-for-service enrollee and the ten counties with the lowest spending per fee-for-service. As a point of reference, average Part A and B spending across all fee-for-service enrollees was $10,546 in 2018 dollars. The top six spending counties are rural counties with an average fee-for-service enrollment of 486. The ten lowest spending counties are also rural counties with an average fee-for-service enrollment of 488. Average spending in the highest spending county, North Slope, AK was $20,584 and was $15,676 higher than the lowest spending county, San Juan County, CO at $4,908. The bottom panel is restricted to counties with total Medicare enrollment above 13,945 enrollees. This restricts the sample to the 780 largest counties of the 3,142 total counties in the US that account for 80% of all Medicare enrollees.

The top 10 spending counties among the large counties had an average total enrollment of 139,824 enrollees, while the lowest 10 spending counties had an average enrollment of 14,311. The average total Medicare enrollment in these larger population counties was 32,938 in 2017. Among the large counties, Baltimore City had the highest spending of $16,781 while Santa Fe County, NM had the lowest average spending of $7,029 for a range of $9,752. These differences in average spending amounts are a function of the relative health, age, income, and demographic characteristics of the counties’ Medicare populations as well as differences in the characteristics of the supply side of the counties’ health care market.

Medicare Advantage Participation
Nationwide, Medicare Advantage, also known as Medicare Part C, enrollment rose from 22.3% of all enrollees in 2007 to 38.2% in 2017. The table below presents the ten counties with the highest and the ten counties with the lowest Medicaid Advantage participation as of 2017, among the subset of the larger counties as defined previously. As seen in the table below, and in the Medicare map, (by selecting Medicare Advantage Participation rate and either the county of state map) Medicare Advantage participation is, as expected - higher in urban areas than in rural areas - and participation is also higher in some states than in others. The top five states in terms of Medicare Advantage participation are: Minnesota at 63%, followed by Hawaii at 53%, Rhode Island at 51%, Oregon at 49%, and California at 48%. The five states with the lowest Medicare Advantage participation rates are Alaska at 1.9%, Wyoming at 4.6%, Vermont at 10.3%, New Hampshire at 12.5%, and Delaware at 13.4%.

Average Risk Scores
Average risk scores are an indication of the relative health of the Medicare enrollees in a given county. The scores are used to adjust payments to Medicare Advantage organizations. The scores are based on an enrollee’s age, sex, eligibility for Medicaid, diagnoses in the prior year, and whether the enrollee lives in a nursing home or was originally qualified due to a disability. The national average risk score each year is normalized to 1. The top panel in the table below presents the ten counties with the highest and the ten counties with the lowest risk scores as of 2017. The bottom panel is restricted to large counties. By comparing the average spending table above to the average risk score table, it is clear that the two measures are correlated. This correlation is also evident by comparing the average spending and average risk score maps. In 2017, the rank correlation coefficient between the two series was 0.55 across all counties and rose to 0.68 when restricted to the larger counties.


Medicaid Eligibility
The percentage of Medicare enrollees who are eligible for Medicaid rose from 20.8% in 2007 to 22.4% in 2011 and dropped to 20.4% in 2017. The rise in the Medicaid eligibility rate between 2007 and 2011 was in part attributable to the recession. The decline in the Medicaid eligibility rate since 2011 is due to the economic recovery and the ongoing entrance of Baby Boomers into the ranks of Medicare enrollees which results in a higher proportion of younger retirees with higher incomes. The top panel in the table below presents the ten counties with the highest and the ten counties with the lowest Medicaid eligibility rates as of 2017. The bottom panel is restricted to large counties.


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Posted: December 11, 2019 by Carlos I. Navarro, Andrew J. Rettenmaier