America’s population is aging across all age groups!

“The nation is aging — more than 4 out of every 5 counties were older in 2018 than in 2010. This aging is driven in large part by baby boomers crossing over the 65-year-old mark. Now, half of the U.S. population is over the age of 38.2,” said Luke Rogers, the Chief of the Population Estimates Branch at the Census Bureau. “Along with this general aging trend, we also see variation among race and ethnicity groups both in growth patterns and aging.” Rogers also noted that alone-or-in-combination groups overlap and individuals who identify as being two or more races are included in more than one of these race groups.

At the state level, North Dakota was the only state to see a decline in its median age, from 37.0 years in 2010 to 35.2 in 2018. Maine had the largest increase in median age this decade, going from 42.7 years in 2010 to 44.9 years in 2018, making it the state with the highest median age in the country. Utah had the lowest median age in 2018, at 31.0 years.

The share of the population age 65-and-older was 16.0 percent in 2018, growing by 3.2 percent (1,637,270) in the last year. The 65-and-older age group has increased 30.2 percent (12,159,974) since 2010. In contrast, during the same period, the under 18 population decreased by 1.1 percent, or a decline of 782,937 people.

Of the nation’s 3,142 counties, 2,566 (81.7 percent) had a higher median age in 2018 than in 2010. During this period, 16.7 percent (525) had median age decreases and 1.6 percent (51) saw no change. In 2018, out of all counties, 56.2 percent (1,767) had a median age between 40 and 49 years. Among those counties with populations of 20,000 or more in 2017 and 2018, Sumter County, Florida, had the highest median age (67.8) and Madison County, Idaho, had the lowest median age (23.2).

As the nation continues to grow older, it is also changing by race and ethnicity. View our graphic on the age and race distribution from 2010 to 2018 to see how the nation has grown more diverse. References below to the race and ethnicity compositions are for race-alone-or-in-combination groups or Hispanic (any race) unless otherwise specified.

• Of the 50 states and the District of Columbia, 20 had a white population of 5.0 million or more, 21 were between 1.0 million and 4.9 million, nine were between 500,000 and 999,999, and one, the District of Columbia, had a population between 100,000 and 499,999.
• In 2018, 18 states had a black population greater than or equal to 1.0 million.
• California was the only state to have an Asian population larger than 5 million, at 6,890,703 in 2018. New York (1,922,974) and Texas (1,688,966) were the only two states that had a population between 1.0 million and 4.9 million.
• The American Indian and Alaska Native population was over 1.0 million in only one state, California, at 1,089,694 in 2018.
• In 2018, 36 states and the District of Columbia had a Native Hawaiian and Other Pacific Islander population that was less than 20,000. The two states with the largest Native Hawaiian and Other Pacific Islander populations in 2018 were Hawaii (382,261) and California (363,437).
• In 2018, the Hispanic population was between 100,000 and 499,999 in 20 states. Among the states and the District of Columbia, 10 states had a Hispanic population of 1.0 million or more. California (15,540,142), Texas (11,368,849), and Florida (5,562,417) were the only states that had populations of 5.0 million or more.

The Hispanic Population (of any race)

• The Hispanic population in the United States grew by 2.0 percent (1,164,289) between 2017 and 2018.
• In 2018, the Hispanic population was greater than or equal to 50,000 in 5.6 percent (177) of counties and less than 100 people in 5.5 percent (173) of counties. Of counties with populations of 20,000 or more in 2017 and 2018, the Hispanic population had the fastest growth in Liberty County, Texas, increasing by 11.4 percent (2,369).
• The Hispanic population was the largest in Los Angeles County, California, with a population of 4.9 million in 2018. The largest numeric growth between 2017 and 2018 was in Maricopa County, Arizona, increasing by 34,395 (2.6 percent) people.

• In 2018, 740 of the 3,142 counties (23.6 percent) had a black or African American population between 1,000 and 4,999 people and 24.1 percent (756) of counties had a black or African American population between 100 and 499 people.
• Cook County, Illinois, had the largest black or African American population, which was about 1.3 million in 2018. Harris County, Texas had the largest numeric increase between 2017 and 2018, gaining 14,017 (1.5 percent) people.
• Of counties with a total population of 20,000 or more in 2017 and 2018, the black or African American population had the fastest increase in Ellis County, Texas, growing by 9.0 percent (1,799) between 2017 and 2018.

• In 2018, 2.7 percent (86) of counties had an Asian population of 50,000 people or more. The Asian population was less than 1,000 people in 73.1 percent (2,297) of counties.
• Los Angeles County, California, had the largest Asian population in 2018 (1,720,889). King County, Washington, had the largest numeric increase in the Asian population, increasing by 23,932 (5.1 percent) between 2017 and 2018.
• Among counties with a total population of 20,000 or more in 2017 and 2018, the Asian population grew the fastest in Forsyth County, Georgia, increasing by 11.5 percent (3,734) between 2017 and 2018.

• In 2018, 20 counties (0.6 percent) had an American Indian and Alaska Native population of 50,000 or more. Also in 2018, 635 counties (20.2 percent) had an American Indian and Alaska Native population between 1,000 and 4,999 and 1,272 (40.5 percent) counties had an American Indian and Alaska Native population that was between 100 and 499. The American Indian and Alaska Native population was less than 1,000 people in 2,219 (70.6 percent) counties.
• Los Angeles County, California had the largest American Indian and Alaska Native population in 2018 (231,340). Maricopa County, Arizona, had the largest numeric increase, growing by 3,745 (2.4 percent).
• Among counties with a total population of 20,000 or more in 2017 and 2018, the American Indian and Alaska Native population had the fastest growth in Clark County, Nevada, increasing by 3.5 percent (1,690) between 2017 and 2018.

• In 2018, only three (0.1 percent) counties had a Native Hawaiian and Other Pacific Islander population of 50,000 or more — these were Honolulu County (245,043) and Hawaii County (70,910) in Hawaii, and Los Angeles County, California (67,730). In 2018, 578 (18.4 percent) counties had a population between 100 and 499 people and 2,217 (70.6 percent) counties had a Native Hawaiian and Other Pacific Islander population that was less than 100 people.
• Honolulu County, Hawaii, had the largest Native Hawaiian and Other Pacific Islander population at 245,043 people in 2018. Clark County, Nevada, had the largest numeric growth, increasing by 1,458 between 2017 and 2018.
• Among counties with a population of 20,000 or more in 2017 and 2018, Pierce County, Washington, had the fastest Native Hawaiian and Other Pacific Islander population increase, growing by 4.9 percent (1,085) between 2017 and 2018.

• The white population remained the largest group in the nation at 78.9 percent (258,080,572), and had the largest numeric increase from 2017 to 2018 (1,055,588).
• In 2018, the white population was greater than or equal to 50,000 in 906 (28.8 percent) counties and between 10,000 and 49,999 people in 1,390 (44.2 percent) of counties. In 2018, 48 (1.5 percent) counties had a white population that was less than 1,000 people.
• Los Angeles County, California, had the largest white population, at 7.4 million in 2018. Maricopa County, Arizona had the largest increase in the white population between 2017 and 2018, growing by 60,749 (1.6 percent).
• Among counties with a population of 20,000 or more in 2017 and 2018, Williams County, North Dakota, had the fastest growth in the white population at 5.3 percent (1,596) between 2017 and 2018.

For additional information about population changes by age and for each race or ethnic group, view our detailed tables. This is the last release of the population estimates for 2018. Previous estimates included national, county, metro area, city and town population estimates. These estimates are as of July 1, 2018, and therefore do not reflect the effects of Hurricane Florence in September 2018, Hurricane Michael in October 2018, and the California Wildfires. For information on how the national population is projected to change through 2060, view our previous release, Older People Projected to Outnumber Children for First Time in U.S. History

Unless otherwise specified, the statistics refer to the population who reported a race alone or in combination with one or more races. Censuses and surveys permit respondents to select more than one race; consequently, people may be one race or a combination of races. The detailed tables show statistics for the resident population by “race alone” and “race alone-or-in-combination.” The sum of the populations for the five “race alone-or-in-combination” groups adds to more than the total population because individuals may report more than one race. The federal government treats Hispanic origin and race as separate and distinct concepts. In surveys and censuses, separate questions are asked on Hispanic origin and race. The question on Hispanic origin asks respondents if they are of Hispanic, Latino or Spanish origin.

Starting with the 2000 Census, the question on race asked respondents to report the race or races they consider themselves to be. Hispanics may be of any race. Responses of “some Other Race” from the 2010 Census are modified in these estimates. This results in differences between the population for specific race categories for the modified 2010 Census population versus those in the 2010 Census data.