The 2020 U.S. Census population figures, delayed by Coronavirus, were posted last month. With the latest figures loaded into our personal computers, here are our further calculations on what the figures mean.

Denver and El Paso County. When it comes to population, the two top dogs in Colorado remain Denver and El Paso County. Keep in mind that two-thirds of the people in El Paso County live in the city of Colorado Springs. Denver and El Paso County were the only two counties in the state to add more than 100,000 persons each from 2010 to 2020. Denver added 115,364 and El Paso County expanded by 108,132.

We calculated each county’s percentage of the total population of Colorado for 2020. Denver was 12.4 percent of Colorado and El Paso County was 12.7 percent. Those figures combine to 25.1 percent. That means one out of every four Coloradans live in either Denver or El Paso County.

We also calculated each county’s percentage of the population growth in Colorado from 2010 to 2020. For the record, 744,518 folks arrived in the state (by birth or transit) in that decade. Denver’s percentage of the state’s newcomers was 15.5 percent and El Paso County’s was 14.5 percent. Those two figures add up to an even 30 percent, and that means almost one in three new Coloradans settled in Denver or El Paso County.

The Colorado economy is fortunate that the state’s two major urban centers – Denver and El Paso County – are attracting new citizens and thus continuing to grow in population. There are many other places where the central cities are static or losing population and thus have gloomy future prospects.

Denver Metropolitan Area. The seven-county Denver Metropolitan Area grew its population substantially from 2010 to 2020. There were 451,694 new arrivals in Denver Metro, which means it now contains 56 percent of the population of Colorado. More important, Denver Metro took in 60.7 percent of the state’s incoming population from 2010 to 2020.

In many ways Colorado is the “city-state” of Denver. That’s the idea that much of what happens of importance in Colorado occurs in the Denver Metropolitan Area, from being the location of the state’ professional sports teams to Denver International Airport (DIA) to leading regional museums and other arts facilities. Denver Metro is population rich and growing and should continue to do so.

The Front Range. The U.S. population is grouping into long population corridors, such as Boston to Washington on the East Coast and Miami to Jacksonville on the Atlantic Coast of Florida. Colorado’s population corridor is the Front Range, that more or less continuous city from Pueblo on the south through Colorado Springs and Denver to Fort Collins and Greeley at the north. It parallels the north-south “front range” of the Rocky Mountains. Interstate-25 is its main highway.

A grand total of 705,877 persons, almost three-fourths of a million, moved into the Front Range of Colorado over the past decade. In 2010, 82.3 percent of Coloradans lived on the Front Range. By 2020 that figure had grown 1.7 points to 84 percent. More startling, 94.8 percent of the population growth in Colorado occurred on the Front Range in 2010-2020.

By 2030 about 86 percent of Coloradans will live on the Front Range. Why not? You get the benefits of living in a well-equipped and economically healthy population corridor with some of the best Rocky Mountain recreation areas just a short drive away.

Ski Counties. Coloradans are fascinated by the counties with major ski resorts high up in the Rocky Mountains. Places such as Aspen (Pitkin County) and Vail (Eagle County) have attracted some of the best educated and wealthiest people in the state. These counties are growing in population but with none of the robustness seen on the Front Range.

We note that the wealthier ski resorts attract many homeowners, probably numbering in the thousands, who have put up second or third homes in these areas but are not counted by the census as living at that location.

From 2010 to 2020 only 16,054 persons made the Ski Counties their new home. They held 4.3 percent of the state’s population in 2010 but, despite the population numbers going up, the Ski Counties were only 4.0 percent of Colorado in 2020. They were outpaced by the rapid population growth on the Front Range, a problem throughout all of the more rural parts of Colorado.

The Ski Counties attracted only 2.2 percent of Colorado newcomers during the past decade.

Western Slope minus the Ski Counties. There are ten counties west of the Continental Divide that have no ski areas, but they grew at about the same pace as the Ski Counties. The fastest growing county on the Western Slope was Mesa County, which contains the city of Grand Junction. Mesa County added 8,980 residents from 2010 to 2020.

Another growing county on the Western Slope was Garfield County, which has the city of Glenwood Springs with its popular hot springs pool. Garfield County grew by 5,296 persons over the past decade.

The Western Slope minus the Ski Counties attracted 2.3 percent of Colorado’s newly arriving residents in the 2010-2020 time period.

Eastern Plains. East of the Rocky Mountains and the Front Range sit the Eastern Plains of Colorado. Thanks to a combination of dry farming, irrigation, and cattle ranching, this is one of the most productive agricultural regions of the state. The population was static from 2010 to 2020, with some counties gaining (Morgan County: plus 952) and other counties losing (Kit Carson County: minus 1,183).

The final figure for this large region, the eastern one-third of the state, was a gain of only 68 persons. The Eastern Plains were 3.2 percent of Colorado’s population in 2010 but dropped to 2.8 percent in 2020.

Southern Colorado. The oldest city in Colorado, San Luis, is located in Southern Colorado. This historic region is famous for its Hispanic population. The San Luis Valley is an important agricultural area in the region.

Southern Colorado lost population from 2010 to 2020 to the tune of 762 fewer citizens. It dropped from 1.4 percent of Colorado’s population to 1.2 percent.

Eastern Mountains. We think of these as the somewhat unnoticed counties of Colorado. They have gorgeous mountain scenery, but because they are on the eastern side of the Continental Divide, they attract much less attention than the Western Slope. This Eastern Mountains region includes Custer County (county seat – Westcliff), Fremont County (Canon City), Chaffee County (Salida), Lake County (Leadville), Park County (Fairplay), Clear Creek County (Georgetown), Gilpin County (Central City), and Jackson County (Walden).

Only 6,202 people moved into the Eastern Mountains from 2010 to 2020. That was only .8 percent of all the newcomers to Colorado for 2010-2020. The region’s percentage of the entire Colorado population dropped from 2.2 to 2.0 percent.

The 2020 Census confirmed that population growth in Colorado is strong but confined mainly to that narrow strip of highly populated land known as the Front Range. Elsewhere in the state, population growth is likely to be moderate or nonexistent.

Tom Cronin and Bob Loevy were longtime Colorado College political science professors who write about Colorado and national politics.