print 
Robert Cushing/Census This chart divides the nation's adult population into four equal groups each decade. The 1st quartile (green line) are the quarter of U.S. adults in the counties with the highest percentage of those over 25 with college degrees. The 4th quarter are those adults living in the counties with the smallest percentage of people with college degrees. You can see that since 1970 the gap between the most and least educated counties has widened significantly as the nation has sorted educationally.
The country is growing increasingly unequal in the location of its educated residents.
The percentage of people in the U.S. who have a college degree has increased dramatically since 1970. Both rural and urban counties have seen a dramatic increase in the percentage of their residents who have at least a college degree.
But the distribution of highly educated people has grown increasingly unequal. People with college degrees are clustering in some counties and not others — a demographic divide with serious economic consequences.
This was not the case 40 years ago. In 1970, the distribution of people with college degrees was fairly even across the country.
Since then, however, counties have become increasingly dissimilar when it comes to educational attainment. In particular, the group of most highly educated counties has zoomed far ahead of everyone else.
You can see that happening in the chart above. Our friend Robert Cushing ranked counties each decade since 1970 by the percentage of adults with a college degree, highest to lowest. Then he divided those counties into four equal groups of adults (those over 25 years of age) — four groups, or quartiles, each with about 50 million people.
The “1st quartile” (green line) represents the counties with the highest percentage of college-educated adults in each decade. The 4th Quartile (orange line) represents the counties with the smallest percentage of college-educated adults.
You can see that in 1970 the top group of counties had 16 percent of adults with at least a college degree while the bottom group of counties had six percent. There was a ten point difference between the top and bottom quartile in 1970.
By 2009, however, the top group of counties had more than 41 percent of adults with college degrees, while the bottom group had risen to 15 percent. The 10-point gap in 1970 had grown to 26 points nearly four decades later.
There are several ways to measure this increasing inequality. The map below shows the distribution of adults (those over 25 years of age) who had a college degree in 2010.
In 2010, 27.9 percent of U.S. adults had a college degree. That’s the national average.
The counties in blue above have a higher percentage, more than 27.9 percent, of their adults with a college degree. Counties in red are at the national average or below.
The darker the blue, the larger the percentage above the national average. Counties that are at least ten percentage points below the national average show up in the darkest red.
There’s a lot of dark red on this map — which means that in 2010, a lot of U.S. counties missed the national average for college degree-holding adults by at least ten percentage points. In fact, 1,652 counties — more than half of all U.S. counties — fell into this category. They all had fewer than 17.9 percent of their adults with college degrees.
Now, look at the map below. This one comes from 1970. In that year, 10.7 percent of U.S. adults had a college degree or better.
The color scheme is the same. Dark red and dark blue counties had either 10 points less or more in terms of adult population with a college degree. As you can see, there is not much dark red or dark blue.
In 1970, 99 percent of all counties were within ten percentage points of the U.S. average of 17.9 percent of adults with a college degree.
In 2010, only 33 percent of U.S. counties were within ten percentage points of the U.S. average.
The small differences between counties of forty years ago have shifted into wide, and widening, differences in education levels by 2010.
The education gap between rural and urban counties in particular has widened. In 1970, 11.6 percent of adults in urban counties had college degrees; by 2010, it was 30 percent.
In 1970, rural counties had 5.6 percent of adults with a college degree, rising to 15.4 percent in 2010.
The difference between rural and urban counties in terms of college attainment jumped from 5.9 percentage points to 14.6 points.
Of the fifty U.S. counties with the highest percentage of adults with college degrees, the only rural counties to be found were Colorado or Wyoming resort communities.
The sorting of college-educated people into a small number of counties has consequences for communities.
“Obviously education is important for the individual, but it’s also important for the community,” said Mark Partridge, a rural economist at Ohio State University. “The higher share of your population that has a bachelors degree, the higher the income of the population. It's good for raising employment growth and wages for everyone."
There is a self-reinforcing pattern at work. Companies increasingly need college-educated workers and so they thrive in places where there are more people with college degrees. As these firms expand, they attract more college graduates into the community — and that in turn spurs development dependent on a highly-educated workforce.
College educated people — many coming out of rural communities — move to places where their degrees are needed, and where those degrees will command the highest pay. That, in turn, spurs more development and more demand for college-educated workers.
Simply having a lot of college-educated people in a rural community is not a sufficient development strategy, says Judith Stallmann, a University of Missouri economist.
"It's a more complex question than many people think it is,” Stallmann said. A lot of people think if only we can get more college educated people in rural areas than, poof, we've solved the problem.”
She continued: “Overall, a highly educated workforce is a necessary but not sufficient condition. If you don't have educated people, in the long run you are going to lose out. But if you have educated people it doesn't guarantee success. It's like Internet access. It's a necessary but not sufficient condition."
Rural communities have to do two things at the same time, Stallmann said: attract college-educated residents and create jobs that demand educated workers.
"We're also going to have to think about how we're going to get those jobs in rural communities, growing them locally,” Stallmann said. “And we have to encourage students who go away to college to come back. How do we do these two things simultaeneously?"
"You have to think about education,” Stallmann said. “But education alone is no guarantee, unless you think about what else you're going to do."
Roberto Gallardo is an assistant extension professor at the Southern Rural Development Center at Mississippi State University. Bill Bishop is co-editor of the Daily Yonder.