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Age and Sex Chapter 4 Age and Sex A ge and sex composition provides a the population pyramids in Figure 4-1. Each of the bars glimpse of a country’s demographic his in the population pyramids represents the percentage tory— reflecting past trends in births, of the total population in that age-sex group. The dis deaths, and migration— as well as a view toward its tribution of the population by age and sex in 1900 demographic future. The age and sex structure of the exhibited the classic pyramid shape, wider at the bot U.S. population affects many of the characteristics tom and narrower at the top. This broad-based shape described in other chapters of this atlas. For example, characterizes a young, relatively high-fertility popula knowing that many Great Plains counties have high tion. In 1900, children under 5 years old accounted for median ages and relatively few young people in their 12 percent of the U.S. population, while people aged populations provides insight into the patterns of popu 65 and older accounted for less than 5 percent. lation decline seen in some maps in Chapter 2. In The low fertility of the Great Depression years is some cases, maps and graphics have been disaggre evidenced by the “pinch” in the age structure in the gated by age or sex to make the impact of these 1950 pyramid, as people born during the 1930s were demographic characteristics more apparent. 10 to 19 years old. By 1950, the onset of the post World War II Baby Boom had altered the bottom of the Changes in Age and Sex Structure pyramid, as 1 1 percent of the population was under The age and sex structure of the U.S. population age 5, giving the second age-sex pyramid a large base of the Census 2000 age-sex pyramid shows the changed during the twentieth century, as shown by of very young people. aging of the U.S. population in the second half of the The more rectangular shape of the lower half twentieth century, due primarily to low fertility fol lowing the Baby Boom. A pinch in the pyramid for Fig u re 4-1. the 20-to-29 age group resulted from the relatively Percent Distribution of Population by Age and Sex, 1900, 1950, and 2000 low number of births during the 1970s. The Baby Boom bulge appears in the 2000 pyramid in the 35to-54-year age range. Another feature of the 2000 85 and older M ale F em a le M ale 1 i[ ■1 ■■ 80 to 84 75 to 79 70 to 74 65 to 69 60 to 64 Fem a le 1 ■ 40 to 44 85 and older 80 to 84 m ]. ■■ H 50 to 54 Fem a le 1 5 5 to 59 45 to 49 M ale 11 ■■ 75 to 79 i ■ age-sex pyramid is the less cone-like shape at the top of the pyramid compared with the 1900 and 1950 70 to 74 pyramids. The larger proportions of the population in 65 to 69 older age groups in 2000 resulted in part from sus 60 to 64 tained low fertility rates and partly from relatively 55 to 59 50 to 54 45 to 49 larger declines in mortality at older ages than at younger ages. 40 to 44 3 5 to 39 35 to 39 Trends in Median Age 30 to 34 30 to 34 Another way of summarizing the overall age struc 2 5 to 29 25 to 29 ture of a population is with its median age— the age 20 to 24 20 to 24 at which half the population is older and half is 15 to 19 15 to 19 10 to 14 10 to 14 Under 5 Under 5 younger. The median age of the population in 1900 was 22.9 years. The median age rose in 8 of the next 6 4 2 0 2 1900 50 4 6 4 2 0 2 1950 4 2 0 2000 2 10 decades, reaching a record high of 35.3 years in 2000 (Figure 4-2). The only two decades of the twen tieth century when the median age did not increase U.S. Census Bureau were 1950-1 960 and 1960-1 970, when Fig u re 4-2. Changes in Sex Ratios, 1900 to 2000 the iarge number of births during the Median Age by Sex, 1900 to 2000 While the overall sex ratio— the number of males per Baby Boom (1946-1964) resulted in a 100 females— in the United States declined during the decline in median age from 30.2 years in twentieth century, a sustained East-West dichotomy is 1950 to 28.1 years in 1970. evident in maps 04-02 through 04-04. In 1900, the sex ratios in most western states were higher than the At the state level, the median age in 2000 was lowest in Utah (27.1 years), U.S. figure of 104.9, and lower sex ratios were found Texas (32.3), Alaska (32.4), and Idaho in states along the Atlantic coast. By 1950, only Alaska (33.2). The median age was highest in and Flawaii had a sex ratio above 105, and West Virginia (38.9), Florida (38.7), Maine Massachusetts had the lowest sex ratio among the 48 (38.6), and Pennsylvania (38.0). States states (93.8). In 2000, the sex ratio for the United with lower median ages in 2000 were States was 96.3, and most states in the eastern half of generally located in the West and the the country had a sex ratio below that figure. South (map 04-01). Growth of the Male and Female Populations Along with the overall rise in median age between 1950 and 2000, the county-level maps of median age in 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 this chapter show distinct geographic Between 1990 and 2000, the male population grew slightly faster (1 3.9 percent) than the female popula patterns. In 2000, the highest median ages occurred were born in Florida. In contrast, many of the counties tion (12.5 percent). In 1990, females outnumbered in counties in the upper Great Plains and the interior in the Northeast and Midwest with older populations males by 6.2 million, a difference that dropped to 5.3 Northeast, and also in Florida, coastal areas of the reflected what is known as “aging in place.” In those million in 2000. This decline resulted in the sex ratio Pacific Northwest, and northern portions of Michigan, areas, the high percentage aged 65 and older was (males per 100 females) increasing from 95.1 in 1990 Wisconsin, and Minnesota. often a result of older people remaining while younger to 96.3 in 2000. The large proportion of those aged 65 and older people migrated elsewhere. Whether the pattern is due Despite this increase, the sex ratio in the United in Florida in 2000 was, in part, the product of a well- to the inmigration of retirees or the outmigration of States decreased during most of the twentieth century. established pattern of retiree migration to that state. young adults, the result is counties with large propor After a peak of 106.2 in 1910, the sex ratio declined Relatively few members (8.9 percent) of this group tions of people 65 and older. to a low of 94.5 in 1980. This long decline resulted U.S. Census Bureau 51 Chapter 4. Age and Sex mainly from the relatively larger reduction in female populations. On the other hand, some counties in the population, with high percentages of the non-Hispanic mortality rates during the period. The sex ratio then Great Plains and Florida have relatively high older White population aged 65 and older in counties in increased between 1980 and 1990, as male death population dependency ratios. Taken together, the Florida, the Great Plains, and parts of the desert rates declined faster than female death rates and as total dependency ratio shows the relationship between southwest (map 04-1 5). The counties with higher more male immigrants than female immigrants the number of people younger than age 18 or 65 and percentages of Blacks who were 65 and older in 2000 entered the country. older to those aged 18 to 64. A handful of counties were located in the South, the Great Plains, and the have ratios of 100 or more, while central Colorado has Ohio River Valley (map 04-16). This Chapter’s Maps a number of counties with a total dependency ratio The maps in this chapter illustrate the age and sex below 40. composition of the U.S. population both historically The percentage of the population under age 18 A series of tract-level maps displays the percent age of the population under age 5 for the country’s largest metropolitan areas (maps 04-1 7 through and in 2000. They also show the geographic distribu varied by race and Hispanic origin in 2000. The Two 04-26). For the United States as a whole, 6.8 percent tion of the young and old populations by race and or More Races population and the Hispanic population of the population in 2000 was under age 5. While the Hispanic origin. Historical maps in the chapter high had the highest percentages under 18 in 2000, at 41.9 tract-level patterns varied among metropolitan areas, light the aging of the U.S. population and the gradual percent and 35 percent, respectively. For the United one pattern was common across all of the metropoli disappearance of high sex ratios in western states. States as a whole, 2 5.7 percent was under age 18. The tan areas: suburban tracts with high percentages Map 04-07 shows patterns of median age by county in 2000. Counties with a high median age are found in Appalachia, much of Florida, the midsection county-level variations in these percentages are seen under age 5 were almost always located in rapidly in maps 04-1 1 through 04-1 3. growing areas with high percentages of new housing The percentage of the population 65 and older and young families. of the country, and the northern Rockies. Counties also varied by race and Hispanic origin in 2000, with with a low median age are seen in Utah and Alaska. the highest percentage found in the non-Hispanic Throughout the country, some individual counties White population (1 5 percent), followed by the Black centages of the total population that were aged 85 have a markedly lower median age than neighboring population (8.1 percent). For the United States as a and older in 2000 (map 04-05), no Arizona or Nevada Some of the chapter’s map patterns may be unexpected. For instance, in the map showing the per counties, due in some cases to the presence of a large whole, 12.4 percent of the population in 2000 was 65 county fell within the two highest percentage ranges, university or military base. and older, and the county-level percentages exhibited although these areas are generally perceived to be a strong geographic concentration (map 04-14). popular destinations for retirees. The maps in the older to the population aged 18 to 64 are shown in Counties with 20 percent or more of their population chapter on migration show that Arizona and Nevada The ratios of people under 18 and people 65 and maps 04-08 through 04-10. Many counties in Utah and aged 65 and older are located in the country’s are indeed magnets for retirees, and at the same time Alaska have high youth dependency ratios, meaning midsection and across much of Florida. The they are also destinations for younger migrants. In that they have larger-than-average numbers of young geographic patterns of the older, non-Hispanic White 2000, the median ages for Arizona (34.2) and Nevada people compared with the sizes of their 18-to-64 population are similar to those of the entire older (35.0) were both below the U.S. median of 35.3 years. 52 U.S. Census Bureau Chapter 4. Age and Sex Population 85 and Older, 2000 4.5 to 6.6 3.0 to 4.4 Percentage of population 85 and older In 2000, 1.5 percent of the U.S. population was 85 and older. The darkest-shaded counties in the map above had 4.5 percent or more of their population in this age group. These counties stretch through the country's midsection from central Texas through Kansas, Nebraska, South Dakota, and North Dakota. They are generally thinly popu lated and rural. The population in many of these counties U.S. Census Bureau declined in recent decades, in part due to the outmigra tion of younger people. Numerous other counties in the Great Plains are in the second- and third-highest categories. Some Florida counties also had relatively high percentages of their populations 85 and older, partly reflecting the large number of retirees who moved to the state. 2.0 to 2.9 1.5 to 1.9 Many metropolitan-area counties have low percent ages of population aged 85 and older. Indeed, visible within the area of darker-shaded counties in the middle of the country are lighter-shaded counties in metropolitan areas such as Dallas-Fort Worth and Minneapolis-St. Paul. Many counties in interior western states also have generally low percentages 85 and older. 53 Chapter 4. Age and Sex 40.0 to 41.9 35.3 to 39.9 U.S. median ~ 30.2 30.2 to 35.2 25.0 to 30.1 20.0 to 24.9 15.2 to 19.9 Data not available Median Age, 2000 45.0 to 58.6 40.0 to 44.9 U.S. median 35.3 35.3 to 39.9 30.2 to 35.2 25.0 to 30.1 20.0 to 24.9 54 U.S. Census Bureau Chapter 4. Age and Sex Older Population Dependency Ratio, 2000 - 60.0 to 96.2 60.0 to 73.7 50.0 to 59.9 Population under 18 years old per 100 people 18 to 64 U.S. Census Bureau U.S. ratio 41.5 41.5 to 49.9 30.0 to 41.4 50.0 to 59.9 40.0 to 49.9 Population 65 and older per 100 people 18 to 64 30.0 to 39.9 20.0 to 29.9 U.S. ratio - 20.1 to 29.9 3.1 to 19.9 20.1 2.6 to 20.0 55 Chapter 4. Age and Sex Under 18 Years, 2000 Under 18 Years, 2000 Hispanic Population Two or More Races Population ■ fM P ~ ■ 60.0 or m ore 60.0 or m ore 50.0 to 59.9 50.0 to 59.9 Percentage of Hispanic population under 18 years old U.S. percent — 35.0 35.0 to 49.9 30.0 to 34.9 Percentage of T w o or M ore Races population under 18 years old U.S. percent 41.9 41.9 to 49.9 30.0 to 41.8 20.0 to 29.9 20.0 to 29.9 Less than 20.0 Less than 20.0 No Two or More Races population 56 U.S. Census Bureau Chapter 4. Age and Sex Percentage of population 65 and older 25.0 to 34.7 20.0 to 24.9 15.0 to 19.9 u.s. 12.4 to 14.9 percent 124 5.0 to 12.3 1.8 to 4.9 65 and Older, 2000 65 and Older, 2000 White Non-Hispanic Population Black Population ■ £ 2 ?- ■ 25.0 or m ore 25.0 or m ore 20.0 to 24.9 Percentage of non-Hispanic W h ite population 65 and older U.S. percent 15.0 to 19.9 15.0 10.0 to 14.9 20.0 to 24.9 Percentage of Black population 65 and older 15.0 to 19.9 8.1 to 14.9 5.0 to 9.9 5.0 to 8.0 Less than 5.0 Less than 5.0 No Black population U.S. Census Bureau 57 Chapter 4. Age and Sex METROPOLITAN AREAS San Francisco-Oakland-San Jose, CA Under 5 Years, 2000 Largest Metropolitan Areas 20.0 to 31.5 13.0 to 19.9 Percentage of population under 5 years old; U .S. m ap b y county, m etropolitan area maps by census tract 10.0 to 12.9 U.S. percent 6.8 6.8 to 9.9 5.0 to 6.7 0.0 to 4.9 No population Boston-WorcesterLaw re nee- Lo w el I - Lo s Angeles-Riverside- * O range C o u n ty 1 \ „o 0 1 100 mi 0 cf 7 GalvestonBrazoria \i 1 j - m 0 200 mi * ' 100 mi 04-17 Los Angeles-Riverside-Orange County, CA 58 Houston-Galveston-Brazoria, TX U.S. Census Bureau Chapter 4. Age and Sex METROPOLITAN AREAS Chicago-Gary-Kenosha, IL-IN-WI Boston-Worcester-Lawrence-Lowell-Brockton, MA-NH Dallas-Fort Worth, TX New York-Northern New Jersey-Long Island, NY-NJ-CT-PA TEX A S P Fort W orth Dallas Philadelphia-Wilmington-Atlantic City, PA-NJ-DE-MD New York NEW JE R S E Y 'Wilmington Atlantic City Atlanta, GA DISTRICT OF .COLUMBIA > Washington, D E L AWA R E Atlanta Washington-Baltimore, DC-MD-VA-WV U.S. Census Bureau 59 Chapter 4. Age and Sex Sex Ratio, 2000 Sex Ratio, 2000 Population Under 18 Population 65 and Older ■SE& - • m m -- More More males 130.0 to 208.3 130.0 to 173.5 N um ber of m ales under 18 years old per 100 fem ales under 18 U.S. ratio 105.2 105.2 to 129.9 100.0 to 105.1 95.0 to 99.9 105.0 to 129.9 100.0 to 104.9 N um ber of m ales 65 and older per 100 fem ales 65 and older 95.0 to 99.9 U.S. ratio 79.0 to 94.9 females 60 70.0 to 94.9 49.9 to 69.9 females U.S. Census Bureau Chapter 4. Age and Sex 25.0 to 192.7 U.S. percent _ change 12.5 12.5 to 24.9 0.0 to 12.4 -10.0 to -0.1 -25.0 t o -10.1 -39.8 to -25.1 U.S. Census Bureau 61 Chapter 4. Age and Sex 45.0 or m ore 45.0 to 64.6 U.S. median 38.6 40.0 to 44.9 38.6 to 44.9 35.0 to 39.9 35.0 to 38.5 30.2 to 34.9 30.0 to 34.9 25.0 to 30.1 25.0 to 29.9 20.0 to 24.9 20.7 to 24.9 Less than 20.0 No Black population Median Age, 2000 Median Age, 2000 American Indian and Alaska Native Population Asian Population • tW - 45.0 or m ore u.s. median 28.0 62 45.0 or m ore 40.0 to 44.9 40.0 to 44.9 35.0 to 39.9 32.7 to 39.9 28.0 to 34.9 30.0 to 32.6 25.0 to 27.9 25.0 to 29.9 20.0 to 24.9 20.0 to 24.9 Less than 20.0 Less than 20.0 No AIAN population No Asian population U.S. Census Bureau Chapter 4. Age and Sex U.S. median 27.5 45.0 or m ore 45.0 or m ore 40.0 to 44.9 40.0 to 44.9 35.0 to 39.9 35.0 to 39.9 27.5 to 34.9 30.0 to 34.9 25.0 to 27.4 2 2 .1 to 29.9 20.0 to 24.9 20.0 to 22.6 Less than 20.0 Less than 20.0 No Pacific Islander population No Two or More Races population Median Age, 2000 Hispanic Population 45.0 or m ore 40.0 to 44.9 35.0 to 39.9 30.0 to 34.9 U.S. median 25.8 25.8 to 29.9 20.0 to 25.7 Less than 20.0 U.S. Census Bureau 63