Alternative Projections of the U.S. population

The U.S. Bureau of the Census recently released a set of population projections that include middle and high projections that we argue are too conservative. The projections discount the possibility of future baby booms and assume slow rates of mortality decline and low levels of immigration. In this article we explore the impact on the size and age composition of the U.S. population of alternative scenarios of plausible fertility, mortality, and immigration assumptions. We conclude that (1) the Census Bureau's highest projection might be interpreted as a reasonable middle projection, (2) a reasonable high projection would yield a U.S. population in 2080 some 300 million persons larger than the Bureau's highest projection, with the population 85 and older more than twice the Bureau's greatest estimate, and (3) uncertainty about the pace of population growth is substantially greater than the Bureau's projections suggest.     

Diverging Demography: Hispanic and Non-Hispanic Contributions to U.S. Population Redistribution and Diversity

The substantial growth and geographic dispersion of Hispanics is among the most important demographic trends in recent U.S. demographic history. Our county-level study examines how widespread Hispanic natural increase and net migration has combined with the demographic change among non-Hispanics to produce an increasingly diverse population. This paper uses U.S. Census Bureau data and special tabulations of race/ethnic specific births and deaths from NCHS to highlight the demographic role of Hispanics as an engine of new county population growth and ethnoracial diversity across the U.S. landscape. It highlights key demographic processes—natural increase and net migration—that accounted for 1990–2010 changes in the absolute and relative sizes of the Hispanic and non-Hispanic populations. Hispanics accounted for the majority of all U.S. population growth between 2000 and 2010. Yet, Hispanics represented only 16 % of the U.S. population in 2010. Most previous research has focused on Hispanic immigration; here, we examine how natural increase and net migration among both the Hispanic and non-Hispanic population contribute to the nation’s growing diversity. Indeed, the demographic impact of rapid Hispanic growth has been reinforced by minimal white population growth due to low fertility, fewer women of reproductive age and growing mortality among the aging white population America’s burgeoning Hispanic population has left a large demographic footprint that is magnified by low and declining fertility and increasing mortality among America’s aging non-Hispanic population.     

The Census Bureau on Prospects for US Population Growth in the Twenty‐First Century

The U.S. Census Bureau periodically releases projections of the US resident population, detailed by age, sex, race, and Hispanic origin. The most recent of these, issued 13 January 2000, for the first time extend to the year 2100 and also include information on the foreign‐bom population. (Earlier projections were carried up to 2080.) The extensive tabulations presenting the new set, and detailed explanation of the methodology and the assumptions underlying the projections, are accessible at the Census Bureau's web site: http://www.census.gov . A brief summary of some of the main results of these projections is reproduced below from United States Department of Commerce News, Washington, DC 20230. (The Census Bureau is an agency of the Department of Commerce.) Uncertainties as to future trends in fertility, mortality, and net migration over a period of some 100 years are very great, as is illustrated by the massive difference in the projected size of the population for 2100 in the three variants produced. The “middle” projected population figure of 571 million (which represents a growth of some 109 percent over its current level) is bracketed by “lowest” and “highest” alternative projections of 283 million and 1.18 billion, respectively. With somewhat lesser force, the point also applies to the 50‐year time span considered in the well‐known country‐by‐country projections of the United Nations. These projections are also detailed in three variants: low, middle, and high. The UN projections (last revised in 1998) envisage less rapid growth in the United States during the first part of the twenty‐first century than do the Census Bureau's. The projected population figures for 2050 in the three variants (low, middle, and high) are as follows (in millions):

State-Level 2010 Census Coverage Rates for Young Children

The Census Bureau’s demographic analysis (DA) shows that the net undercount rate for children aged 0–4 was 4.6 percent in the 2010 U.S. Decennial Census while adults (age 18 and older) had a net overcount rate of 0.7 percent. For the population aged 0–4, DA estimates are seen as more accurate than the U.S. Decennial Census because the estimates for this young population rely heavily on highly accurate birth certificate data. Given the relatively high net undercount rate for young children, it would be useful to examine census coverage rates for this population in subnational geographic units. In this study, the 2010 U.S. Decennial Census counts of children aged 0–4 are compared to the corresponding figures from the Census Bureau’s Vintage 2010 Population Estimates in each state. Differences between the 2010 U.S. Decennial Census count and the Vintage 2010 Population Estimates for the population aged 0–4 range from an estimated net undercount of 10.2 percent in Arizona to an estimated net overcount of 2.1 percent in North Dakota. Larger states tended to have higher net undercounts than smaller states. The ten largest states account for about 70 percent of the national net undercount of the population aged 0–4. Of all the factors examined here, the relative size of the Blacks Alone or in Combination plus Hispanics population is most highly correlated with the estimated net undercount of the population aged 0–4. Other measures that were highly correlated with net undercount rates for the population aged 0–4 were linguistic isolation, percent of adults without a high school degree, and the unemployment rate. In general, characteristics of people are more highly correlated with the net undercount rates of young children than the characteristics of housing units.     

U.S. population in the 21st century: Which scenario is reasonable?

A major Census Bureau study released in January 1989 has evoked renewed warnings in the media and among some population analysts that the U.S. faces population decline in the next century if it does not increase fertility and/or raise immigration. The report's middle scenario rests on an assumed future total fertility rate (TFR) of 1.8, life expectancy of 81.2 years, and net immigration of 500,000 annually. These mid-range assumptions would yield a United States population of 268 million by 2000, peaking at 302 million in 2040 and falling to 292 million by 2080. Questionable assumptions in the report's most likely scenario are discussed. These are:

1. that immigrants bear children at the same rate as their equivalent age and racial group in the United States population.
2. that the high TFR of Hispanics will not raise the overall 1.8 TFR foreseen for whites as the Hispanic proportion of the white population continues to grow.
3. that net yearly immigration will fall to 575,000 in 1990 and 500,000 by 2000. The Census Bureau's "high" assumption of 800,000 net yearly may be more realistic.

The report's low growth scenario projects future population size that is more reassuring than alarming: 264 million in 2000, rising to 288 million in 2030, and falling to 266 million in 2080. Thus, in ninety years the United States would still have 20 million more people than now. While some fear that such slow growth will lower United States influence and bring labor shortages and an aging population, the nation's quality of life would be less at risk with a population of 266 million than with one approaching the one-half billion projected by the Census report's high estimates.     

Immigrants’ ages and the structure of stationary populations with below-replacement fertility

A sustained regime of low fertility plus immigration yields an unusual kind of stationary population. The author demonstrates that all stationary populations have a common structure, and that the familiar replacement-level fertility population is the youngest among the many stationary populations corresponding to a particular life table. This finding has important consequences for policy because although fertility increase and immigration are equally effective at halting population decline, immigration is inferior as a means of rejuvenating low-fertility populations. In fact, an immigration-based policy could make a low-fertility population older rather than younger. The paper includes examples using U.S. and West German vital rates.     

Making the Housing Unit Method Work: An Evaluation of 2010 Population Estimates in Florida

The housing unit (HU) method—in which population estimates are derived from estimates of occupied HUs—is the most commonly used method for making small-area population estimates in the United States. It is widely used because it is conceptually simple, can utilize a wide variety of data sources, can be applied at virtually any level of geography, and often produces reliable estimates. Yet the HU method is more nearly a general approach to population estimation than it is a specific methodology. In this paper, we describe and evaluate several data sources and estimation techniques that can be used in applying the HU method. Using a set of county and subcounty estimates produced by the Bureau of Economic and Business Research (BEBR) at the University of Florida for April 1, 2010, we analyze errors by population size and growth rate, calculate errors for each of the three components of the HU method, and investigate the accuracy of estimates based on several different data sources and estimation techniques. We compare the accuracy of the 2010 estimates with previous BEBR estimates and estimates produced by the U.S. Census Bureau. We conclude that although some data sources and estimation techniques work better than others, the HU method can be tailored to produce reliable population estimates for a wide variety of geographic areas.     

Reconstructing the size of the African American population by age and sex, 1930–1990

We estimate the size of the African American population in five-year age groups at census dates from 1930 to 1990 using a three-part strategy. For cohorts born after 1935, we follow the U.S. Census Bureau in using classical demographic analysis. To estimate the size of cohorts born before 1895, we use extinct-generation estimates. For remaining cohorts, we implement an age/period/cohort model of census counts. All approaches are applied to a data set in which the age distribution of deaths has been corrected for age misreporting. Results provide strong confirmation of the basic validity of Census Bureau estimates of census undercounts for African Americans while extending estimates to new cohorts and periods. Our estimates are less consistent with an historical series prepared by Coale and Rives (1973).     

The equivalence of united states census data for persons of Russian stock or descent with American Jews: An evaluation

While the U.S. Bureau of the Census has had a long-standing policy of abstaining from enumerating the religious beliefs or backgrounds of the American people, at least two-thirds of the Jewish population of the United States has been enumerated in decennial censuses and sample surveys in the guise of persons of Russian stock or origin. This has come about through the migration policy of the old Russian Empire and the statistical categories utilized by American immigration authorities and by the U. S. Bureau of the Census for immigrants and their children. Comparisons between the returns from an ethnic survey and a survey on the religious composition demonstrate the close congruence between persons of Russian stock or descent and American Jews on the national level.     

Coverage of the population in Census 2000: Results from Demographic Analysis

Since the 1960 Census, Demographic Analysis (DA) has been used by the Census Bureau to evaluate the coverage of the population. Administrative statistics on births, deaths, immigration and Medicare enrollments as well as estimates of legal emigration and net undocumented immigration are used to produce demographic analysis estimates of the population for the census date. These estimates are compared to the Census 2000 data to evaluate coverage in the census. The results are also compared to measures of undercount obtained from dual system estimation. The DA measures substantial reduction in net undercount in Census 2000 compared to 1990. The reductions occur among all demographic categories: all broad age groups, males and females, Blacks and Non-Blacks.     

Population Trends in Metropolitan and Nonmetropolitan America: Selective Deconcentration and the Rural Rebound

This study uses revised annual population estimates that incorporate adjustments from the 2000 Census to backcast demographic change for U.S. counties during the 1990s. These data are supplemented with new post-censal population estimates for 2001–2003. We use these data to examine demographic trends in the late 1990s and first years of the new century. Our findings are consistent with a model suggesting that a selective deconcentration of the U.S. population is underway. Our findings also confirm the occurrence of the rural rebound in the first half of the 1990s and a waning of this rebound in the late 1990s. Post-censal data also suggest a modest upturn in nonmetropolitan population growth rates in 2001–2003.     

美国2000年人口普查结果初析

美国２０００年人口普查初步结果已于２０００年１２月底公布。从公布的初步结果看到，美国人口在９０年代出现了很多变化，这些变化也多是历史演变趋势的继续。根据美国人口统计局从去年底至今年４月初陆续公布的数据和报告，可以分析出９０年代美国人口的最新变化。     

The Environmental Impact of Immigration: An Analysis of the Effects of Immigrant Concentration on Air Pollution Levels

Despite growing interest in the impact of immigration on U.S. society, research has rarely examined the effects of immigration flows on the natural environment. The current study addresses this gap in research using data on 183 Metropolitan Statistical Areas drawn from the Environmental Protection Agency, the U.S. Census Bureau, and the National Oceanic and Atmospheric Administration to empirically assess the relationships between contemporary immigration and seven measures of air pollution. In doing so, we seek to (1) broaden knowledge about the social consequences of immigration to include its potential effects on the environment, (2) address competing theoretical perspectives about immigration-environment relationships (i.e., population pressure/social disorganization versus ecological footprint/community resource perspectives), and (3) extend knowledge about the predictors and sources of environmental harm within local communities. In contrast to popular opinion and population pressure positions, our research indicates that immigration does not contribute to local air pollution levels across any of the seven pollution measures examined.     

Immigration data and national population estimates for the United States

The immigration component in national population estimates is comparatively small, but it is not insignificant and may indeed be an important source of error. Therefore, it warrants the considera-tion of those concerned with population estimates. The paper considers alternative methods for deriving estimates of immigration from the raw data and presents estimates of net immigration from 1950 to 1965. They are developed from estimates previously published by the Bureau of the Census, but they differ at some points where new data have become available or where a review of the data has led to a change in judgment on how best to use them. The paper also presents suggestions on how immigration statistics might be altered for purposes of improving the estimates.Census data may be used to estimate net immigration by three different methods, but upon analysis each method proves to be inadequate. Hence, data based on visas surrendered at the port of entry must be the principal source of immigration estimates. These data have their limitations because (1) they do not cover net arrivals of citizens from abroad and from Puerto Rico, (2) they do not report departures of aliens, and (3) they do not allocate all immigrants to year of entry. Alien registration and passenger data offer possible alternative estimates.The paper attempts to measure unrecorded immigration, discusses how net arrivals of citizens from abroad and from Puerto Rico may be estimated, and how the age, sex, and race of immigrants may be treated.     

Same-Sex Married Tax Filers After <Emphasis Type="Italic">Windsor</Emphasis> and <Emphasis Type="Italic">Obergefell</Emphasis>

This article provides new estimates of the number and characteristics of same-sex married couples after U.S. Supreme Court rulings in 2013 and 2015 established rights to same-sex marriage. The U.S. Department of the Treasury and the Internal Revenue Service subsequently ruled that same-sex spouses would be treated as married for federal tax purposes. Because almost all married taxpayers file joint tax returns, administrative tax records provide new information on the demographic characteristics of married same-sex couples. This study provides estimates of the population of same-sex tax filers drawn from returns filed in 2013, 2014, and 2015, using methods developed by the U.S. Census Bureau to address measurement error in gender classification. We estimate that approximately 0.48 % of all joint filers in 2015 were same-sex couples, or approximately 250,450 couples.     

How responsive is U.S. population growth to immigration? A situational sensitivity analysis

There has been public concern about the effect of immigration on population growth in the U.S. But how responsive is population growth to immigration? This paper examines the sensitivity of intrinsic population growth to immigration and situates such sensitivity in fertility and survival changes. The application of second derivatives on a modified Leslie matrix facilitates the analysis of situational sensitivity of U.S. population growth to immigration. The results show that the sensitivity to immigration is not as influential as the sensitivity to fertility, and that the sensitivity to immigration further depends on changes in fertility and survival.     

Immigration and the stable population model

This paper reports on work aimed at extending stable population theory to include immigration. Its central finding is that, as long as fertility is below replacement, a constant number and age distribution of immigrants (with fixed fertility and mortality schedules) lead to a stationary population. Neither the level of the net reproduction rate nor the size of the annual immigration affects this conclusion; a stationary population eventually emerges. How this stationary population is created is studied, as is the generational distribution of the constant annual stream of births and of the total population. It is also shown that immigrants and their early descendants may have fertility well above replacement (as long as later generations adopt and maintain fertility below replacement), and the outcome will still be a long-run stationary population.     

A consideration of the effect of immigration reform on the number of undocumented residents in the United States

The volume of immigration to the United States exceeds the amount of immigration to any other nation, but quantification must rely on measurement of population stocks. Comparison of foreign-born population figures for two or more survey dates reveal net immigration but fail to partition the foreign-born population by legal status. This analysis presents national survey data on the foreign-born population in November 1989 for comparison with an independently derived estimate of the legally resident foreign-born population at the same date. The demonstration of a measurable undocumented population residing in the United States is very helpful in evaluating the success of the Immigration Reform and Control Act of 1986. Despite the legalization of 1.7 million aliens who provided evidence of undocumented residence since before 1982, and economic sanctions against employers found to hire undocumented workers, an undocumented population persists in the United States that appears to be largely composed of aliens from Latin American countries. Precise measurement of the size of this population is complicated by the uncertainties surrounding the population of approximately one million Special Agricultural Workers admitted under IRCA. The work and residence history of these aliens as well as their future labor sector experiences and residence patterns are not known. Despite efforts to stop undocumented immigration to the United States, undocumented migration, especially across the southern border, appears to have occurred at consistent levels throughout the past fifteen years.This paper reports the general results of research undertaken by Census Bureau staff. The views expressed are attributable to the author and do not necessarily reflect those of the Census Bureau.     

Post-disaster fertility: Hurricane Katrina and the changing racial composition of New Orleans

Large-scale climate events can have enduring effects on population size and composition. Natural disasters affect population fertility through multiple mechanisms, including displacement, demand for children, and reproductive care access. Fertility effects, in turn, influence the size and composition of new birth cohorts, extending the reach of climate events across generations. We study these processes in New Orleans during the decade spanning Hurricane Katrina. We combine census data, ACS data, and vital statistics data to describe fertility in New Orleans and seven comparison cities. Following Katrina, displacement contributed to a 30% decline in birth cohort size. Black fertility fell, and remained 4% below expected values through 2010. By contrast, white fertility increased by 5%. The largest share of births now occurs to white women. These fertility differences—beyond migration-driven population change—generate additional pressure on the renewal of New Orleans as a city in which the black population is substantially smaller in the disaster’s wake.