A Decade of Population Growth and Decline in U.S. Counties

There are a number of factors that determine how much a region’s population changes.

If an area sees a high number of migrants, along with a strong birth rate and low death rate, then its population is bound to increase over time. On the flip side, if more people are leaving the area than coming in, and the region’s birth rate is low, then its population will likely decline.

Which areas in the United States are seeing the most growth, and which places are seeing their populations dwindle?

This map, using data from the U.S. Census Bureau, shows a decade of population movement across U.S. counties, painting a detailed picture of U.S. population growth between 2010 and 2020.

Counties With The Biggest Population Growth from 2010-2020

To calculate population estimates for each county, the U.S. Census Bureau does the following calculations:

 
From 2010 to 2020, Maricopa County in Arizona saw the highest increase in its population estimate. Over a decade, the county gained 753,898 residents. Below are the counties that saw the biggest increases in population:

Phoenix and surrounding areas grew faster than any other major city in the country. The region’s sunny climate and amenities are popular with retirees, but another draw is housing affordability. Families from more expensive markets—California in particular—are moving to the city in droves. This is a trend that spilled over into the pandemic era as more people moved into remote and hybrid work situations.

Texas counties saw a lot of growth as well, with five of the top 10 gainers located in the state of Texas. A big draw for Texas is its relatively affordable housing market. In 2021, average home prices in the state stood at $172,500—$53,310 below the national average.

Counties With The Biggest Population Drops from 2010-2020

On the opposite end of the spectrum, here’s a look at the top 10 counties that saw the biggest declines in their populations over the decade:

The largest drops happened in counties along the Great Lakes, including Cook County (which includes the city of Chicago) and Wayne County (which includes the city of Detroit).

For many of these counties, particularly those in America’s “Rust Belt”, population drops over this period were a continuation of decades-long trends. Wayne County is an extreme example of this trend. From 1970 to 2020, the area lost one-third of its population.

U.S. Population Growth in Percentage Terms (2010-2020)

While the map above is great at showing where the greatest number of Americans migrated, it downplays big changes in counties with smaller populations.

For example, McKenzie County in North Dakota, with a 2020 population of just 15,242, was the fastest-growing U.S. county over the past decade. The county’s 138% increase was driven primarily by the Bakken oil boom in the area. High-growth counties in Texas also grew as new sources of energy were extracted in rural areas.

The nation’s counties are evenly divided between population increase and decline, and clear patterns emerge.

Pandemic Population Changes

More recent population changes reflect longer-term trends. During the COVID-19 pandemic, many of the counties that saw the strongest population increases were located in high-growth states like Florida and Texas.

Below are the 20 counties that grew the most from 2020 to 2021.

Many of these counties are located next to large cities, reflecting a shift to the suburbs and larger living spaces. However, as COVID-19 restrictions ease, and the pandemic housing boom tapers off due to rising interest rates, it remains to be seen whether the suburban shift will continue, or if people begin to migrate back to city centers.

Mapping the Migration of the World’s Millionaires

Throughout 2022, a projected 88,000 millionaires will move to a new country, according to the latest Henley Global Citizens Report.

Which countries are these millionaires moving to, and where in the world are they coming from?

This graphic maps the migration of high net worth individuals (HNWIs)—people with a net worth of over US$1 million—showing where rich people are flocking, and where they’re fleeing.

Migration of Millionaires is Back

Before diving into the country-specific data, it’s worth taking a step back to look at overall millionaire migration trends, and how things are changing this year.

2020 saw a drastic drop in the number of millionaire migrants, as pandemic-induced lockdowns kept people from leaving their home countries—and at times, their homes in general.

But as restrictions ease and countries begin to open up their borders again, the migration of millionaires is beginning to gather steam once again:

Below, we’ll dive into which countries are seeing the highest number of HNWI migrants, and which ones are losing the most HNWIs.

Which Countries Are Millionaires Leaving?

There are a plethora of reasons why the ultra-rich move countries. Escaping conflict is one of them, which is why it’s no surprise to see Russia and Ukraine are projected to see some of the biggest emigration numbers by the end of 2022.

Here are the top 10 countries by millionaire outflows:

Figures rounded to the nearest 100.

While Russia is expected to see 15,000 millionaires leaving the country, Ukraine is projected to experience the highest loss in percentage terms—a whopping 42% of its HNWIs could leave the country by the end of 2022.

China could also see a big loss in its millionaire population, with a projected loss of 10,000.
According to Andrew Amoils, Head of Research at New World Wealth, this could be more damaging to the country than in previous years, since general wealth growth in China has declined recently.

Where Are The Ultra-Rich Moving?

The United Arab Emirates (UAE) has become a millionaire magnet, with a projected 4,000 HNWIs flowing into the country by the end of 2022. This influx of ultra-wealthy people is partly because of the country’s accommodating immigration policies that are specially tailored to attract private wealth and international talent.

Here are the top 10 countries that saw millionaire inflows:

Australia continues to attract HNWIs, coming in second behind the UAE. According to New World Wealth, approximately 80,000 millionaires have moved to the Land Down Under in the last two decades.

A few things that attract migrants to Australia are the country’s low costs of healthcare, its lack of inheritance tax, and its generally prosperous economy.

Update: This article and graphic have been updated to more clearly explain what’s being shown, and list the data source in a more prominent way. We appreciate your feedback.