News of the 2020 census has been dribbling out for many months, but analyses of the masses of data have been overshadowed by other events — not least, of course, the Covid-19 pandemic, which actually delayed the processing of the census itself. Now, with time to crunch numbers and reflect, it is possible to draw some conclusions that point toward what America is becoming in the 21st century.

While big demographic changes have been brewing for decades, they now contrast more sharply with the last half of the 20th century than ever before. We have become a nation characterized by sluggish population growth and, above all, by growing racial and ethnic diversity. In fact, were it not for the gains in the nonwhite population — especially Hispanics, Asian Americans and those who identify with two or more races — the U.S. population would have shrunk over the past decade and become even more top heavy in its age structure than it is today. Here are some major takeaways from the 2020 census, and key numbers that buttress them.

The 2010s Saw the Second Lowest Population Growth in U.S. History

The 331,449,281 U.S. residents counted in the 2020 census represent a population increase of 7.4 percent from the 2010 count of 308,745,538. The pace of growth is the second slowest decadal rate since the first census was taken in 1790 — barely faster than the 7.3 percent growth in the 1930s during the Great Depression. And it was roughly half the 13.2 percent growth rate of the 1990s, when immigration was high and the last members of the big millennial generation were born.

The 2010s registered declines in births, increases in deaths and lower immigration levels compared with the decade prior. Immigration was reduced by tougher federal restrictions that led to an overall decline in the non-citizen foreign-born population. And low natural increase levels (fewer births, more deaths) reflect, in part, delays in marriage and childbearing among the economically bludgeoned millennials, along with a rise in drug and pandemic-related deaths. Meanwhile, the U.S. population continues to age, and Census Bureau projections show that this will reverberate through the next decades as a further reduction in natural population growth. It seems pretty clear that the nation will need to increase immigration if we wish to prevent population growth from turning negative.

Slow population growth is reflected in state-by-state figures, albeit not uniformly. Three states (West Virginia, Mississippi and Illinois) lost population from 2010 to 2020. This is the largest number of population-losing states since the 1980s, when depopulation was driven by the decline of manufacturing jobs in the Rust Belt. In the prior two decades, only one state (Michigan, from 2000 to 2010) lost population.

All told, 37states experienced slower growth over the 2010-20 decade than in the previous decade, and all 50 exhibited slower growth than in the high-flying 1990s. Economically depressed West Virginia showed the greatest rate of population loss (3.2 percent) during the 2010s, which was brought on by a combination of natural decrease (more deaths than births) and accelerated out migration.

Perhaps more surprising, while California continued to grow, the pace was just 6.1 percent, the slowest in its history. The Golden State’s slowdown reflects both reduced immigration from abroad and net out-migration, arguably a consequence of the scarcity of affordable housing near job-plentiful cities.

Sun Belt States Grew Fastest in This Slow Growth Environment

States in the South and West mostly fared better than average. At the high end were several Mountain West states as well as Texas and Florida. Among the former, Utah, Idaho, Nevada and Arizona had all shown high growth across the previous two decades as well. But a closer look reveals some important variations. Nevada, whose population ballooned by a stunning 66 percent in the 1990-2010 years, slowed to 15 percent in 2010-20, reflecting the housing crunch of the financial crisis and the Great Recession that hit the desert cities particularly hard.

The one non-Sun Belt state among these fast-growers is outlier North Dakota, where growth rose to 15.8 percent (up from just 4.7 percent in 2000-10). This was largely due to in-migration during the shale oil and gas boom in the early 2010s.

Even in the slow-growth 2010s there was a continuation of the long-term migration trend toward the Sun Belt. The 1970 census showed that less than half of the U.S. population resided in the South (31 percent) and the West (17 percent). Indeed, the South’s share was only slightly higher than the Midwest’s. But in the half-century that followed, the Sun Belt’s share rose to 62 percent, with the South and West regions each gaining 7 percentage points. Meanwhile, the population shares of the Midwest and Northeast each fell by 7 percentage points.

By no coincidence, several Sun Belt states improved their population-size rankings over the 2010-20 decade. Florida overtook New York to become the third largest state, Georgia and North Carolina overtook Michigan to become the eighth- and ninth-largest states, while Arizona passed Massachusetts and Indiana to become the 14th-largest state.

A First-Time Decline in the White Population

One especially notable result of the 2020 census is the absolute decline in the number of U.S. residents who identify as white (rather than as Hispanic or other racial groups). This is the first decline since the first census was taken in 1790. Indeed, during much of the nation’s history, white population growth mirrored the national growth rate. Yet, since the 1970s, white growth has been marked by a continued tail-off, reaching just 1.2 percent in 2000-10. In the following decade, the white population fell by a remarkable 2.6 percent — over 5 million people.

Lower fertility and slower immigration played a part here, but much of this loss was attributable to the continued aging of the white population. Fewer births and more deaths resulted in a natural decrease for the 2010s decade, even before Covid-19 added to mortality. Note, too, that the figures are affected by the rise of multiracial marriages, which has led to an increase in the number of young people who identify as mixed race rather than white.

Thus, nonwhite race and ethnic groups accounted for all of the 2010 to 2020 gains in the U.S. population. The biggest contributions came from Hispanics at 11.6 million — representing roughly half of the nation’s total decadal gain. Asian-Americans and persons identifying with two or more races were also large contributors to the total decade population gain.

Although only three states registered net population losses over the 2010-20 decade, fully 35 states experienced white population losses. Among the 32 states that still gained population in spite of losses of whites, nonwhite race and ethnic groups drove all of the 2010s growth. A good example is California, which led the nation in white losses (1.2 million) but saw large gains in Hispanic (1.5 million) and Asian-Americans (1.2 million). It’s worth pointing out, too, that white population declines were pervasive in America’s cities as well, with 61 of the 100 largest metropolitan areas showing losses.

Racial- And Ethnic-Group Gains Were by No Means Uniform

Black population gains were concentrated in the Sun Belt states, led by Texas, Georgia and Florida. This is consistent with the recent history of Black migration to prosperous Southern states, countering the “great migration” of African-Americans from the South in the first half of the 20th century. Yet several non-Southern states, including Minnesota, Nevada and Arizona, have also attracted Black residents over the past decade. At the other end of the spectrum are seven states along with the District of Columbia that registered losses in Black residents. The largest losses occurred in Illinois, California, Michigan and New York — the primary sources of the reverse migration back to the South.

States that gained the most Hispanic and Asian-American residents are generally the ones that have historically attracted immigrants from these populations, including Texas, California, Florida and New York. Although both Hispanics and Asian-Americans are now dispersing across the country, overall gains are still heavily clustered in these states.

More Than Two-Fifths of Americans Now Identify as People of Color

The 2020 census numbers mark a diversity milestone in that a substantial plurality (over 42 percent) of Americans now identify with one or more nonwhite racial and ethnic groups.

The past several censuses had already revealed the trend toward increased diversity. In 1980, white residents comprised almost 80 percent of the nation’s residents, with Blacks accounting for 11.5 percent and Hispanics 6.4 percent. By 2000, the Hispanic population had passed the Black population — 12.5 percent versus 12.1 percent. By then, the Asian- American share was also growing (to 3.6 percent), while the white share had dropped to 69.1 percent.

Twenty years on, the white population share slipped further to 57.8 percent, while the Hispanic and Asian-American shares have risen to 18.7 percent and nearly 6 percent, respectively. Strikingly, while the shares of whites, Hispanics and Asian-Americans have fluctuated considerably over the past four decades, the Black share has remained nearly constant.

Especially notable shifts have taken place in urban counties including Queens County, NY; Cook County, Ill.; Harris County, Tex.; Gwinnett, Ga. (suburban Atlanta) and Solano, Calif. (Bay Area). In these counties, Asian- American, Black, and Hispanic populations constitute larger percentages of the county population than they do nationally.

More generally, Hispanic residents are well represented in a broad range of counties from California to Texas, as well as parts of the Mountain West, the Southeast, urbanized parts of the North, and many smaller places in the nation’s interior. Asian-Americans are found in substantial numbers in California, Washington, Texas, portions of the Southeast, large metropolitan areas and small towns in all parts of the country — and often in the same places as other nonwhite groups.

Fully 58 percent of the nation’s Black population resides in the South. High concentrations of Black residents are also found in many northern urban counties and, together with other nonwhite groups, in parts of the West. The much smaller Native American population is highly represented, often with other groups, in Oklahoma, Alaska, portions of the Mountain West, and the Upper Great Plains. (By “highly represented” I mean when a group comprises a higher share of the total population than for the nation as a whole.)

Although the map does show notable swaths of “white” counties where no nonwhite racial or ethnic group is significantly represented, many of these are small and sparsely populated where the population is stagnating. As a group, these white counties — which occupy large sections of the middle of the country — are home to just three out of 10 of all U.S. residents. In contrast, about onethird of U.S. residents live in counties where two or more nonwhite racial or ethnic groups are highly represented, with the remainder living in areas where one is highly represented. All told, 95 percent of all counties registered declines in their white population shares during the 2010-20 decade

Youth Population on the Wane

A key finding from the 2020 census is the overall decline in the nation’s under-age-18 population. The decadal loss of over one million young people contrasts with gains in that cohort during the previous two decades. While this is not the first decade to register a decline in the under-18 numbers, the circumstance differs from that in the 1960s, when much of the large baby-boomer cohort was under age 18 and comprised 35 percent of the total population. Now the youth share, which represents only 22 percent of Americans and has been declining in 27 states, is facing the responsibility of supporting a tsunami of retirees in the near future.

People of Color Comprise Over Half the Nation’s Youth

Because immigrants and their U.S.-born children are younger on average than other households, recent decades’ immigration (mostly from Latin America and Asia) has served to partly offset the white youth decline. Indeed, were it not for Hispanics, Asian- Americans and mixed-race groups, the past decade’s decline in youth would have been much larger. This was not a statistical fluke: the white youth population is projected to decline in decades to come.

This pattern occurred in most states. Indeed, all states except Utah and North Dakota (and the District of Columbia) showed 2010- 20 declines in white youth. However, in 21 of those — including Texas and Florida, the states with the largest overall gains in young residents — white youth losses were more than offset by gains in youths of color. Because the vast majority of states also show losses in their Black and Native American under-18 populations, youth gains tend to come largely from Hispanics, Asians or persons identifying with two or more races. For the first time, whites represented less than half (47.3 percent) of the under-18 population.

In 2020 half of the youth population in 21 states and over 40 percent in an additional eight states were people of color. In several Southern states, spread from Louisiana to Virginia, African American youths make up the largest nonwhite share. However, in a number of states in the West (California, Arizona, New Mexico and Nevada) and South (Texas and Florida), Hispanic youths are highly represented.

State Population Shifts May No Longer Favor Republicans

The reason the U.S. Constitution mandates a decennial census is that it is needed to allocate the number of congressmen each state sends to the House — which since 1920 has had 435 seats. Thus, when a new census is taken, some seats are reapportioned to take into account changing relative state populations.

Only seven seats changed states on the basis of the 2020 census — the smallest number since the 1940s. All of the states gaining seats are in the South and West. The winners: Texas (2), Florida, Colorado, Montana, Oregon and North Carolina.

Five of the states losing one seat each (Illinois, Michigan, Ohio, New York and Pennsylvania) are in the Midwest and Northeast. The other two are West Virginia and California.

California is noteworthy from a historical standpoint. Prior to this census, the Golden State had never lost a seat from reapportionment. In fact, it gained seats (often multiple seats) from 1920 to 2000, when it reached its peak of 53 representatives — the largest state delegation in the House. After the 2010 census, California neither gained nor lost seats; now, for the first time, its delegation will be pared.

The new reapportionment puts recent Sun Belt population gains in historical perspective. Over the past 100 years, three Sun Belt states — California, Florida and Texas — gained the most congressional seats due to reapportionment, with additions of 41, 24 and 20 seats, respectively. However, in the most recent three decades, many Sun Belt population gains have occurred in the interior parts of the West and South, as migrants and new immigrants began to disperse within these regions. The cumulative shifts in seats over this period have given multiple seats not only to Texas and Florida, but also to Arizona, Georgia, Colorado, Nevada and North Carolina.

The impact of this shift in presidential elections is worth a closer look, as reapportionment has also increased the Electoral College clout of these particular states. As recently as 2000, each of these seat-gaining Sun Belt states voted fairly consistently for Republican candidates in presidential elections. However, the demographics of each have changed in ways that have already shifted (or may soon shift) them to the Democratic column. So, while the reapportionment additions to Sun Belt states have long been seen to favor Republican presidential contenders, this is not as likely to be the case down the road.

Looking Ahead

The decennial census is the gold standard for definitive statistics about the nation’s population. And the 2020 census makes clearer than any previous survey that, while slow-growing and aging, the nation is rapidly becoming more racially and ethnically diverse — especially among its young.

The impact is playing out in varying ways across the states and metros. But it’s clear that most places still attracting more people than they lose are becoming more racially and ethnically diverse. And the trend is not weakening.

Moreover, it is becoming clear that as the nation’s overall population growth continues to lose momentum — and at an accelerated pace as a result of the pandemic — we need to look to migrants from outside our borders to sustain prosperity. The 2020 census makes plain that in the 21st century America’s economic and demographic growth will increasingly depend on younger, more racially diverse workers and taxpayers to hold back the tides of entropy.