Reversal: Big Metro Counties Lose Population

Population growth in the United States ground to a halt during the pandemic. Between July 1, 2020, and June 30, 2021, the population grew by just 0.1 percent, according to Census Bureau estimates. This is the slowest rate of growth in the nation's history. 

The coronavirus pandemic explains the slow growth. Because of Covid, deaths exceeded births in a record high 73 percent of the nation's counties. Because of Covid, the number of net international migrants to the United States plunged, falling to just 247,000 in 2020–21, down from 477,000 in 2019–20. For context, net international migration was as high as 1,049,000 in 2015–16.

The pandemic also messed with domestic migration, consequently reversing the long-standing pattern of population growth by Rural-Urban Continuum. The Rural-Urban Continuum (RUC) is the federal government's system of classifying counties by their degree of urbanity. It is a useful tool for analyzing growth patterns at the county level. The RUC is a scale ranging from 1 (the most urban counties, in metropolitan areas of 1 million or more) to 9 (the most rural counties, lacking any settlements of 2,500 or more people and not adjacent to a metropolitan area).

The long-term pattern during the 2010s was one of urban growth—the more urban, the greater the growth. But this was not the case in 2020–21, according to a Demo Memo analysis. Counties with a rank of 1 on the continuum (the most urban) lost population during the year. Every other county type grew at least a bit, even the most rural. Here is how county populations changed in 2020–21 by rank on the Rural-Urban continuum...

County population change by Rural-Urban Continuum rank, July 1, 2020–June 30, 2021
1. -0.16% for counties in metros with 1 million or more people
2.  0.62% for counties in metros of 250,000 to 1 million people
3.  0.47% for counties in metros with less than 250,000 people
4.  0.36% for nonmetro counties with urban pop of 20,000-plus, adjacent to metro
5.  0.06% for nonmetro counties with urban pop of 20,000-plus, not adjacent to metro
6.  0.29% for nonmetro counties with urban pop of 2,500–19,999, adjacent to metro
7.  0.04% for nonmetro counties with urban pop of 2,500–19,999, not adjacent to metro 
8.  0.63% for nonmetro counties with urban pop less than 2,500, adjacent to metro 
9.  0.28% for nonmetro counties with urban pop less than 2,500, not adjacent to metro 

Behind the population loss in big metro counties is the one-two-three punch of the pandemic. Births fell, deaths increased, and the trickle of net international migrants could not make up for domestic migration losses in some of the largest metros such as New York, San Francisco, Los Angeles, and Chicago.

Source: USDA, Economic Research Service, Rural-Urban Continuum Codes and Census Bureau, County Population Totals: 2020–2021

Center of Population Still in Missouri

The center of population is still in Missouri, the Census Bureau reports. The center's latitude and longitude place it 14.6 miles northeast of the tiny town of Hartville. The center has been ambling through Missouri since 1980. Every decade after completing the census, the Census Bureau calculates the mean center of population. It defines the mean center "as the place where an imaginary, flat, weightless and rigid map of the United States would balance perfectly if all residents were of identical weight." It's imaginary, but instructive. 

Between 2010 and 2020, the center of population moved only 11.8 miles. This is the shortest distance the center has moved since 1920 and the second shortest distance ever, the Census Bureau reports. It is also the most southerly move ever. "This southerly drift and shorter distance can be attributed to a strong pull on the center by continued population growth in the Southeast," the Census Bureau explains.

The Census Bureau also calculates the mean center of population for states and counties. You can see your state and county centers of population and how far they moved between 2010 and 2020 on this data visualization. 

Source: Census Bureau, Census Bureau Announces Hartville, Missouri as "Center of Population" for the United States

Less Educated Counties are Falling Behind

The U.S. population is getting better educated. But only in some places and not in others. Among the nation's 3,138 counties, the 58 percent majority are becoming better educated. The remaining 42 percent are educationally stagnant—they have not experienced a statistically significant increase in educational attainment over the past decade, according to a Census Bureau analysis of five-year American Community Survey data from 2005–09 to 2015–19.  

Forty-two percent is a lot of counties—more than 1,000. The bad news doesn't stop there. A disproportionate share of the stagnant counties were the least educated to begin with. This means there is a growing gap between counties not only in educational attainment, but also in the economic opportunities that accrue to educated populations. 

To do its analysis, the Census Bureau divided counties into two educational attainment groups. The measure of educational attainment was the percentage of county residents aged 25 or older with a bachelor's degree in 2005–09. For all counties at the time, 18.7 percent of residents aged 25 or older had a bachelor's degree. One educational attainment group consisted of all counties that fell below this threshold. The other group was all counties above this threshold. Now for the analysis: among the counties that fell below this threshold in 2005–09, only 49.8 percent experienced an increase in educational attainment by 2015–19. Among the counties that were above this threshold in 2005–09, a much larger 78.6 percent experienced an increase in educational attainment during the next 10 years. 

This is not good news for stagnant counties. It means the socioeconomic gap between counties is growing, the rural-urban divide is widening, and struggling counties will find economic prosperity even more elusive. 

The coronavirus pandemic will only exacerbate these problems. Recently released Bureau of Labor Statistics projections of the labor force impact of the pandemic show jobs disappearing for less-educated Americans. The number of jobs available for those without a high school diploma is projected to drop 2.3 percent between 2019 and 2029 because of the pandemic, according to a New York Times analysis of the Bureau of Labor Statistics' Covid-impact projections. Pre-Covid, these jobs had been projected to grow. The number of jobs available to those with a high school diploma and no further education will inch up by only 0.1 percent in the decade ahead, far less growth than foreseen pre-Covid. At the other extreme, Covid will boost job growth for the better educated. For those with a bachelor's degree, jobs will increase 6.7 percent—a bit more than forecast pre-Covid. Similarly, the job market for people with a graduate degree will expand 9.7 percent during the decade, also above the pre-Covid forecast. 

All this means we need to prepare for more friction, more turmoil—political and otherwise—between educationally stagnant and educationally advancing counties as these trends unfold.

Source: Census Bureau, Bachelor's Degree Attainment in the United States: 2005 to 2019

48% of Counties Lost Population, 2018–19

The U.S. population grew by just 0.48 percent in the year ending July 1, 2019. This is the slowest annual rate of growth in 100 years. Growth has actually ground to a halt in many places. According to the Census Bureau's latest estimates, 48 percent of the nation's 3,142 counties lost population between 2018 and 2019.

Even in counties with growing populations, expansion is slowing. The slowdown is occurring everywhere—from the largest urban areas to the most remote rural outposts. A handy way to analyze growth patterns at the county level is by using the federal government's Rural-Urban Continuum, a system of classifying counties by their degree of urbanity. The Continuum is a scale ranging from 1 (the most urban counties, in metropolitan areas of 1 million or more) to 9 (the most rural counties, lacking any settlements of 2,500 or more people and not adjacent to a metropolitan area).

The long-term pattern since 2010 has been one of urban growth—the more urban, the greater the growth. But an examination of the trend in annual growth rates reveals some changes. Counties with a rank of 1 on the continuum (the most urban) grew faster than any other county type in every year between 2010 and 2017. But in 2018 and 2019, the growth rate of rank 1 counties slipped below that of rank 2 counties. Another change has occurred in nonmetropolitan counties. Counties ranking 6 and 8 on the Rural-Urban Continuum had been steadily losing population for most of the decade, but in 2017 they began to record small gains which continued in 2018 and 2019. The gains have not been large enough, however, to make up for losses earlier in the decade. Here are county growth rates for the decade and for the past year by rank on the Rural-Urban continuum...

County population change 2010-2019 (and 2018–19) by Rural-Urban Continuum rank
1. 8.0% (0.54) for counties in metros with 1 million or more people
2. 6.7% (0.64) for counties in metros of 250,000 to 1 million people
3. 4.4% (0.38) for counties in metros with less than 250,000 people
4. 0.6% (0.17) for nonmetro counties with urban pop of 20,000-plus, adjacent to metro
5. 1.6% (0.10) for nonmetro counties with urban pop of 20,000-plus, not adjacent to metro
6. –1.0% (0.01) for nonmetro counties with urban pop of 2,500–19,999, adjacent to metro
7. –1.6% (-0.18) for nonmetro counties with urban pop of 2,500–19,999, not adjacent to metro 
8. –1.0% (0.10) for nonmetro counties with urban pop less than 2,500, adjacent to metro 
9. –2.2% (-0.21) for nonmetro counties with urban pop less than 2,500, not adjacent to metro 

Behind the widespread slowing of population growth is the ongoing baby bust, the aging of the baby-boom generation, and the decline in net migration—both domestic and international. With population growth already slowed to a crawl before coronavirus swept the nation, the percentage of counties recording population losses in 2020 is likely to be greater than the 48 percent of 2019. 

Source: USDA, Economic Research Service, Rural-Urban Continuum Codes and Census Bureau, County Population Totals and Components of Change: 2010–2019

County Population Trends, 2010 to 2018

Between 2010 and 2018, the nation's most urban counties grew faster than any other county type, according to the Census Bureau's county population estimates. A Demo Memo analysis of 2010-to-2018 county population trends along the Rural-Urban Continuum documents ongoing metro growth and continuing rural decline. But patterns are changing.

The Rural-Urban Continuum is the federal government's way of classifying counties by their degree of urbanity. The continuum is a scale ranging from 1 (the most urban counties, in metropolitan areas of 1 million or more) to 9 (the most rural counties, lacking any settlements of 2,500 or more people and not adjacent to a metropolitan area). If you sort the nation's 3,000-plus counties by their rank on the continuum, then measure population change between 2010 and 2018 for each rank, this is the result...

County population change 2010-2018 by Rural-Urban Continuum Rank
1. 7.6% for counties in metros with 1 million or more people
2. 6.2% for counties in metros of 250,000 to 1 million people
3. 4.1% for counties in metros with less than 250,000 people
4. 0.5% for nonmetro counties with urban pop of 20,000-plus, adjacent to metro
5. 1.7% for nonmetro counties with urban pop of 20,000-plus, not adjacent to metro
6. –1.0% for nonmetro counties with urban pop of 2,500–19,999, adjacent to metro
7. –1.6% for nonmetro counties with urban pop of 2,500–19,999, not adjacent to metro 
8. –1.0% for nonmetro counties with urban pop less than 2,500, adjacent to metro 
9. –1.9% for nonmetro counties with urban pop less than 2,500, not adjacent to metro 

The long-term pattern has been one of urban growth—the more urban, the greater the growth. But an examination of annual growth rates reveals important changes. Counties with a rank of 1 on the continuum (the most urban) grew faster than any other county type in every year between 2010 and 2017. But between 2017 and 2018, the growth rate of rank 1 counties slipped below that of rank 2 counties—an increase of 0.72 percent for rank 1 counties versus a slightly larger 0.75 percent increase for rank 2 counties. Behind the slower growth of rank 1 counties are small declines between 2017 and 2018 in the populations of the three largest metro areas —New York, Los Angeles, and Chicago. 

Conversely, some nonmetropolitan counties that had been steadily losing population are now making small gains. Rank 6 and 8 counties grew slightly in both 2017 and 2018, but those gains were not large enough to make up for losses earlier in the decade.  

Source: USDA, Economic Research Service, Rural-Urban Continuum Codes and Census Bureau, County Population Totals and Components of Change: 2010–2018

County Extremes: Health Insurance Coverage

The percentage of Americans aged 21 to 64 who do not have health insurance varies greatly by county, according to the Census Bureau's small area health insurance estimates. At one extreme is Norfolk County, Massachusetts, where only 2.6 percent of people aged 21 to 64 were not insured in 2016. At the other extreme is Hidalgo County, Texas, where 40.9 percent were not insured.

A look at the Census Bureau's interactive map accompanying the data reveals Texas to be a hot spot of the uninsured. Of the 10 counties in the nation with the highest percentage of people aged 21 to 64 who are uninsured, all are in Texas. At the other extreme, 7 of the 10 counties with the smallest percentage of uninsured are in Massachusetts.

Source: Census Bureau, Small Area Health Insurance Estimates

Baby Bust Is Hurting Rural America

Forty percent of the nation's 3,000-plus counties have experienced more deaths than births since 2010, according to the Census Bureau's latest county population estimates. The aging of the population (more deaths), drug overdoses (more deaths), and the ongoing baby bust (fewer births) has resulted in negative natural increase (births minus deaths) in huge swaths of the country.

Rural areas have been hit particularly hard by the one-two punch of more deaths and fewer births. Negative natural increase is a big reason for the population decline in many rural counties. Nearly half or more of the counties ranking 6, 7, 8, and 9 on the Rural-Urban Continuum experienced more deaths than births in the 2010-to-2017 time period.

The Rural-Urban Continuum (RUC) is the federal government's way of classifying counties by their degree of urbanity. The continuum is a scale ranging from 1 (the most urban counties, in metropolitan areas of 1 million or more) to 9 (the most rural counties, lacking any settlements of 2,500 or more people and not adjacent to a metropolitan area). If you sort the nation's 3,000-plus counties by their rank on the continuum, then measure the percentage of counties in each rank in which deaths outnumbered births from 2010 to 2017, this is the result...

Percent of counties with more deaths than births by RUC rank, 2010-2017
1. 13.2% of counties in metros with 1 million or more people
2. 26.7% of counties in metros of 250,000 to 1 million people
3. 27.5% of counties in metros with less than 250,000 people
4. 34.1% of nonmetro counties with urban pop of 20,000-plus, adjacent to metro
5. 23.9% of nonmetro counties with urban pop of 20,000-plus, not adjacent to metro
6. 48.6% of nonmetro counties with urban pop of 2,500–19,999, adjacent to metro
7. 48.7% of nonmetro counties with urban pop of 2,500–19,999, not adjacent to metro 
8. 68.3% of nonmetro counties with urban pop less than 2,500, adjacent to metro 
9. 59.1% of nonmetro counties with urban pop less than 2,500, not adjacent to metro 

The most urban counties were least likely to have negative natural increase—only 13 percent of big-city counties experienced more deaths than births since 2010.

Source: USDA, Economic Research Service, Rural-Urban Continuum Codes and Census Bureau, County Population Totals and Components of Change: 2010–2017

Counties Without Businesses

Some of the nation's 3,142 counties lack certain essential businesses. These "business deserts" were tallied recently by the Census Bureau's Andrew W. Hait, using data from the bureau's 2015 County Business Patterns...

Number of counties lacking employer establishments
Gas stations: 22
Commercial banks: 37
Religious organizations: 42
Grocery stores: 48
Offices of lawyers: 215
Child care services: 287
Dentist's offices: 305
Doctor's offices: 344
Hardware stores: 489
Beauty salons: 802
Drinking places: 926
Movie theaters: 1,586

While counties may have no employer establishments, Hait notes, their populations may be served by nonemployers—independent contractors and sole proprietors. He cites the example of child care service. While 2,855 counties in the U.S. have at least one employer child care service, a larger 3,117 have nonemployer (home-based) child care services.

Source: Census Bureau, Filling the Void in Counties Lacking Key Businesses

Migration Fuels Urban County Growth

The nation's most urban counties grew by a substantial 6.0 percent between 2010 and 2016, faster than any other type, according to a Demo Memo analysis of the Census Bureau's 2016 county population estimates by Rural-Urban Continuum (RUC). Counties in smaller metros grew at a slower rate, and those in rural areas lost population. Both international and domestic migration contributed to the faster growth of big-city counties...

International migration is greater in big-city counties. Between 2010 and 2016, the rate of net international migration was 2.6 percent in counties ranking 1 on the Rural-Urban Continuum. Although international migration was positive in every type of county, the rate was lower in less urban counties and lowest (only 0.3 percent) in the most rural counties—those ranking 8 or 9 on the RUC.

Domestic migration is positive only in big-city counties. Between 2010 and 2016, the rate of net domestic migration was positive only for counties ranking 1 or 2 on the Rural-Urban Continuum. Nonmetropolitan counties (those ranking 4 or higher on the RUC) had a negative rate of net domestic migration, meaning they lost more people than they gained.

Source: USDA, Economic Research Service, Rural-Urban Continuum Codes and Census Bureau, County Population Totals Datasets: 2010–2016

Health Status by Rural-Urban County Classification

The larger and more dense the urban county, the greater the percentage of residents who practice healthy habits, according to a study by the CDC. The habits examined by the CDC were smoking, drinking (moderately or not at all), maintaining normal body weight, meeting aerobic physical activity recommendations, and getting enough sleep. While differences by type of county were not large, they were statistically significant...

Percent of resident who practice at least 4 of 5 healthy behaviors, by county type
Large metropolitan center counties: 31.7%
Large fringe metropolitan counties: 30.2%
Median metropolitan counties: 30.5%
Small metropolitan counties: 29.5%
Micropolitan counties: 28.8%
Rural counties: 27.0%

Even after controlling for demographic characteristics, the pattern is the same. "Evidence-based strategies to improve the health-related behaviors of persons living in rural areas in the United States should be widely implemented," the report concludes.

Source: CDC, Health-Related Behaviors by Urban-Rural County Classification—United States, 2013

Big-City Counties Continue to Attract Migrants

The nation's most urban counties grew by a substantial 5.3 percent between 2010 and 2015, faster than any other type, according to a Demo Memo analysis of the Census Bureau's 2015 county population estimates by Rural-Urban Continuum. Counties in smaller metros grew at a slower rate, and those in rural areas lost population. Every component of population change is driving the growth of the most urban counties...

Natural increase is greater in big-city counties. Between 2010 and 2015, the rate of natural increase (defined as births minus deaths) was 2.8 percent in counties ranking 1 on the Rural-Urban Continuum (in metro areas with populations of 1 million or more). This was a higher rate of natural increase than any other type of county on the continuum. Counties ranking an 8 or 9 (the most rural) had a negative rate of natural increase, with deaths outnumbering births.

International migration is greater in big-city counties. Between 2010 and 2015, the rate of net international migration was 2.3 percent in counties ranking 1 on the Rural-Urban Continuum. International migration was positive in every type of county, but the rate was lower in less urban counties and was lowest (0.2 percent) in counties ranking 8 or 9.

Domestic migration is greater in big-city counties. Between 2010 and 2015, the rate of net domestic migration was positive only for the most urban counties,  ranking 1 or 2 on the Rural-Urban Continuum. Less urban and rural counties lost more domestic migrants than they gained.

Big-City Counties Growing the Fastest (Still)

The nation's most urban counties continue to grow faster than any other county type according to the Census Bureau's 2015 county population estimates. A Demo Memo analysis of 2010-to-2015 county population trends along the Rural-Urban Continuum documents strong metro growth (the bigger, the better) and continuing rural decline.

The Rural-Urban Continuum is the federal government's way of classifying counties by their degree of urbanity. The continuum is a scale ranging from 1 (the most urban counties, in metropolitan areas of 1 million or more) to 9 (the most rural counties, lacking any settlements of 2,500 or more people and not adjacent to a metropolitan area). If you sort the nation's 3,000-plus counties by their rank on the continuum, then measure population change between 2010 and 2015 for each rank, this is the result...

County population change 2010-2015 by Rural-Urban Continuum Rank
1. 5.3% for rank 1 counties, in metros with 1 million or more people
2. 3.9% for rank 2 counties, in metros of 250,000 to 1 million people
3. 2.6% for rank 3 counties, in metros with less than 250,000 people
4. 0.1% for rank 4 counties, nonmetro adjacent to metro with urban pop of 20,000+
5. 1.7% for rank 5 counties, nonmetro not adjacent to metro with urban pop of 20,000+
6. -0.8% for rank 6 counties, nonmetro adjacent to metro with urban pop of 2,500-19,999
7. -0.5% for rank 7 counties, nonmetro not adjacent to metro with urban pop of 2,500-19,999
8. -1.1% for rank 8 counties, nonmetro adjacent to metro with urban pop less than 2,500
9. -1.2% for rank 9 counties, nonmetro not adjacent to metro, urban pop less than 2,500

The most urban counties (a 1 on the scale) grew the fastest between 2010 and 2015. The most rural counties (8 and 9 on the scale) experienced the biggest declines. A look at annual rates of population change by Rural-Urban Continuum shows declines in every year between 2010 and 2015 for counties ranking 6, 7, 8, and 9 on the continuum. Counties with a rank of 1 on the continuum grew by more than 1 percent in every year. 

Source: USDA, Economic Research Service, Rural-Urban Continuum Codes and Census Bureau, Population Estimates, County Total: Vintage 2015

Find the Recreation Hot Spots

Where are the nation's recreation hot spots and retirement destinations? Which local economies are dependent on manufacturing, mining, farming, or federal and state government employment? The USDA's Economic Research Service has new maps and stats that reveal the economic and social characteristics of the nation's 3,000-plus counties.

"The 2015 County Typology Codes classify all U.S. counties according to six mutually exclusive categories of economic dependence and six overlapping categories of policy-relevant themes," explains the ERS. The results are downloadable as an Excel spreadsheet.

Source: USDA Economic Research Service, 2015 County Typology Codes

Most Nonmetro Counties Are Losing Population

Two-thirds of the nation's nonmetropolitan counties lost population between 2010 and 2014, according to the USDA's Economic Research Service. The number of nonmetro counties with declining populations reached an historic high of 1,310 in the 2010-14 time period.

Population decline is caused by two factors: more people moving out than in, and more deaths than births. The number of nonmetro counties experiencing the "double jeopardy" of net-outmigration and natural decrease climbed from 387 in 2003-07 to 622 in 2010-14.

According to a Demo Memo analysis of population growth by metropolitan status, the nation's largest metropolitan areas, with a population of 1 million or more, grew 4.2 percent between 2010 and 2014. Smaller metropolitan areas grew 2.7 percent. Nonmetropolitan counties as a whole lost 0.2 percent of their population during those years.

Source: USDA Economic Research Service, Two-Thirds of U.S. Nonmetro Counties Lost Population over 2010-14

Most U.S. Population Growth is in Drought-Stricken Counties

More than half the nation's population growth since 2000 has occurred in drought-stricken areas of the United States, according to a study by the Brookings Institution. From 2000 to 2014, fully 57 percent of the nation's population increase occurred in counties experiencing drought. Among the 10 counties with the biggest population gain over the time period, 7 are experiencing drought.

Source: Brookings Institution, Population Surging in Drought-Stricken Areas

What's Behind the Gains for Big-City Counties?

The nation's most urban counties grew by a substantial 4.2 percent between 2010 and 2014, faster than any other type, according to a Demo Memo analysis of the Census Bureau's 2014 county population estimates by Rural-Urban Continuum. Counties in smaller metros grew at a slower rate, and those in rural areas lost population. Every component of population change is driving the growth of the most urban counties...

Natural increase was greater in big-city counties. Between 2010 and 2014, the rate of natural increase (defined as births minus deaths) was 2.4 percent in counties ranking 1 on the Rural-Urban Continuum (in metro areas with populations of 1 million or more). This was a higher rate of natural increase than any other type of county on the Continuum. Counties ranking an 8 or 9 on the Continuum (the most rural) had a negative rate of natural increase between 2010 and 2014—deaths outnumbered births in those areas.

International migration was greater in big-city counties. Between 2010 and 2014, the rate of net international migration was 1.8 percent in counties ranking 1 on the Rural-Urban Continuum. While net international migration was positive in every type of county, the rate fell with declining urbanity to a low of just  0.1 to 0.2 percent for counties ranking an 8 or 9.

Domestic migration was greater in big-city counties. Between 2010 and 2014, the rate of domestic migration was positive only for the most urban counties—those ranking a 1, 2, or 3 on the Rural-Urban Continuum. Less urban counties lost more migrants than they gained.

Big-City Counties Grew the Most

The nation's most urban counties continue to attract Americans by the millions, according to the Census Bureau's 2014 county population estimates. A Demo Memo analysis of 2010-to-2014 county population trends along the Rural-Urban Continuum documents strong city growth (the bigger, the better) and unrelenting rural decline.

The Rural-Urban Continuum is the federal government's way of classifying counties by their degree of urbanity. The continuum is a scale ranging from 1 (the most urban counties, in metropolitan areas of 1 million or more) to 9 (the most rural counties, lacking any settlements of 2,500 or more people and not adjacent to a metropolitan area). If you sort the nation's 3,142 counties by their rank on the continuum, then measure population change between 2010 and 2014 for each rank, this is the result...

County population change 2010-2014 by Rural-Urban Continuum Rank
1. 4.2% for rank 1 counties, in metros with 1 million or more people
2. 3.0% for rank 2 counties, in metros of 250,000 to 1 million people
3. 2.1% for rank 3 counties, in metros with less than 250,000 people
4. 0.1% for rank 4 counties, nonmetro adjacent to metro with urban pop of 20,000+
5. 1.4% for rank 5 counties, nonmetro not adjacent to metro with urban pop of 20,000+
6. -0.7% for rank 6 counties, nonmetro adjacent to metro with urban pop of 2,500-19,999
7. -0.5% for rank 7 counties, nonmetro not adjacent to metro with urban pop of 2,500-19,999
8. -1.4% for rank 8 counties, nonmetro adjacent to metro with urban pop less than 2,500
9. -0.9% for rank 9 counties, nonmetro not adjacent to metro, urban pop less than 2,500

The most urban counties (a 1 on the scale) grew the fastest between 2010 and 2014. The most rural counties (8 and 9 on the scale) experienced the biggest declines.

Source: USDA, Economic Research Service, Rural-Urban Continuum Codes and Census Bureau, Population Estimates, County Totals: Vintage 2014

Hotter Temps = Lower Incomes

Global warming may reduce incomes in the United States, according to a National Bureau of Economic Research study (NBER Working Paper 20750, $5). In an analysis of 40 years of U.S. county-level data, the researchers find a productivity decline of 1.7 percent for every 1.8°F  rise in daily average temperature. "A weekday above 30°C (86°F) costs an average county $20 per person," they report, noting: "Hot weekends have little effect."

Magnets for Millennials

Young adults are packing their bags and moving to the city. The nation's most urban counties gained more than 1 million 25-to-34-year-olds between 2008-10 and 2011-13, according to a Demo Memo analysis of the American Community Survey. This numerical gain is nearly double the increase in the number of 25-to-34-year-olds in all other counties combined.

There's more: The most urban counties, with a rank of 1 on the Rural-Urban Continuum (in metro areas with a population of 1 million or more), also saw the largest percentage increase in 25-to-34-year-olds between 2008-10 and 2011-13—a 4.5 percent rise. In the most rural counties, with a rank of 9 on the Rural-Urban Continuum, the number of 25-to-34-year-olds fell 4.8 percent during the time period.

Artists by County

1.6 million artists are at work in the United States, according to the USDA's Economic Research Service. Artists include not only painters and sculptors but also designers, actors, producers, directors, athletes, dancers, musicians, and entertainers. Artists account for 1.1 percent of the nation's workers.

• Of the nation's 3,143 counties, more than 90 percent have at least one working artist. Only 290 counties have no artists.
• San Juan County, Colorado, has a higher percentage of artists in its workforce than any other county—6.5 percent. The county is sparsely populated, with 460 employed residents, which is why its 30 artists account for such a large share. 
• Los Angeles County has more artists than any other. The 121,620 artists who live in the county account for 2.7 percent of its workforce. New York County (Manhattan) has a smaller number of artists (44,765), but they are a larger share (5.3 percent) of its workforce.

Source: USDA, Economic Research Service, Creative Class County Codes