Demography and Demographics

Summary

Demography and demographics both involve the study of human populations. Demography refers to the discipline of measuring and analyzing factors about groups of people, such as group size, composition, density, and growth. These factors may be studied at a single point in time or followed over years. Demographics commonly refers to the factors themselves but can also mean the study of populations as a discipline. Many demographers work in professional fields related to marketing. Others seek to understand populations to predict political activity, such as voting patterns, public health trends, or the expansion and decline of cities.

Definition and Basic Principles

Demography is the study of human populations and the ways in which they grow and change over time. Although a population might be a group of people as small as a single rural village, most demographic studies look at groups living in a metropolitan area, a region, or even a country or continent. Demographers are also likely to use data categories such as age, family status, ethnicity, household size, education, and income level in answering questions about population change.

Three primary factors govern changes in population size. Fertility is the rate at which new members of the population are born. Migration shows the rate at which members move in and out of the population during their lifetimes. Mortality is the rate at which population members die. Demography is the social science in which these factors, along with many others, are analyzed to better understand why a population is growing or declining.

Demographics refers to the data gathered by demographic analyses. Government agencies are some of the leading users of demographic data as they create and implement public policy. Companies also rely on demographic data as they design products and services for growing markets.

Background and History

Philosophers and scholars have discussed ideas about population growth for thousands of years. In ancient Greece, Plato and Aristotle advocated the concept that civilizations should strive to reach certain population levels determined by the maximum quality of life that could be achieved under such numbers. Both Plato and Aristotle examined questions about migration, population and the environment, and fertility control. Similar issues were explored by writers in China and India.

Demography was further developed in Europe in the sixteenth through eighteenth centuries under a school of thought known as mercantilism. Under mercantilism, population growth was seen as a necessary force behind the increase of a country's trading power and wealth. In 1798, this philosophy was challenged by British professor Thomas Malthus, who anonymously published "An Essay on the Principle of Population," in which he argued that human biology would, by nature, create a future society that would be overpopulated and struggle with heightened problems such as poverty and famine.

Many nineteenth-century demographers such as William Farr and Louis-Adolphe Bertillon made advancements in the field through their work in public health. By the late 1800s, statistical analysis had become a key component of demographic study. Actuarial science, led by insurance providers to better understand mortality and risk, also contributed to the discipline.

How It Works

Demographic studies seek to answer questions about human populations. To conduct a study, demographers must define their questions and design a survey or census to collect the necessary data. Once the data are gathered, demographers apply statistical tools to measure and analyze the information. The results allow demographers to determine whether their question has been answered or whether further research is needed.

Question Definition. Every demographic study begins with a question about a group of people that can be answered by data analysis. A well-designed study needs a question that is thoroughly defined. For example, a city's board of education might ask, "How many students are expected to attend public school in the city each year over the next ten years?" Demographers working for the board would choose the items to be measured in the study and define each item in detail, such as the number of days in a year that a student would need to be present at school to be counted.

Study Design and Data Collection. Once the question is defined, demographers decide what sources of data to use and how to collect the information. Many demographic studies rely on census data, which involves gathering information on each member of a population. Census data are thorough but difficult and expensive to compile. Many demographers instead rely on surveys, which collect information from people chosen as a representative sample of the population. The survey data are analyzed statistically to infer conclusions about the population as a whole. In the example of the school board, the demographers might gather data through a census or survey of households with at least one child younger than nine years.

Measurement and Analysis. Demographers use tools that store the information gathered in surveys or censuses and assist with statistical analysis. The demographers in this example might transfer their survey data into a database or other application that would allow them to create multiyear growth forecasts. Additional information might come from population growth projections for the city or region. The demographers would use this information to compensate for areas not covered by the survey, such as households where there are not yet any children or households living outside the city limits at the time of the survey's mailing. Once these sources of data are combined and analyzed, demographers document their findings and make recommendations about additional research, if needed.

The types of data gathered by demographers often fall into categories. Fertility measures the rate at which a population grows because of the number of babies being born to population members. Migration is the rate at which people join or leave a population by moving to new homes inside or outside its borders. Immigration refers to people moving into an area, while emigration describes people leaving the area. Some studies follow patterns known as domestic migration, in which people move from one part of an area to another. Mortality measures a population's rate of death. Aside from these categories, demographers seek to understand factors such as the distribution of age and sex across a population. These factors are particularly important when using population data to build forecasts.

Applications and Products

Demographic data are used in a wide range of contexts. Some of the most common tools for demographic research are population census data, social surveys, and commercial and marketing surveys.

Population Census Data. Countries throughout the world track the number of people living within their borders. Most national governments have a department or agency that uses a tool such as a census to gather information. Census data are used by other government agencies to track population growth, decline, and migration. Aggregate data from censuses are often published by governments for use by businesses and the public. These data are released in the form of reports and electronic databases. In many countries, a full population census is conducted roughly once every five to fifteen years. Some countries gather population data more regularly, while others do not conduct a census of all residents but use statistical sampling to estimate information about their populations.

Social Surveys. Social surveys are conducted on selected members of a population to gather data that will be used to understand the population as a whole. Although they present a higher rate of error than a census, they cost less and can be carried out more quickly. Many large-scale social surveys focus on specific issues such as education, housing, employment, or health. Others are focused on geography. The American Community Survey from the Census Bureau is one of the best-known social surveys in the United States. The United Nations conducts many social surveys focused on both topic and region, such as the economic and social survey of Asia and the Pacific.

Commercial and Marketing Surveys. Demographic information about groups of people is useful to companies as well as government agencies. Commercial and marketing surveys gather some of the same types of data as social surveys. Companies focusing on a new target market or expanding their hold on an existing group of customers are likely to track factors such as average age, ethnic background, family structure, education, and income levels. When analyzed, these factors are used to guide the company's decisions about which products and services to offer and how to communicate them to the customers most likely to buy them. Market data publisher Nielsen's Pop-Facts reports are an example of demographic data available commercially.

Areas of Focus. Professionals working within the field of demography often hold jobs that require them to focus by subject area. Common areas in which demographers are employed are public health and epidemiology, immigration and emigration policy, and urban and environmental planning.

Public Health and Epidemiology. Demographers working in the field of public health and epidemiology seek to answer questions such as which public health problems pose the greatest risk to a population, based on its age structure and sex ratio, and what factors will define a population's public health needs in ten to twenty years. They conduct surveys to gather data, which they may combine with other sources, such as statistics from hospitals, to assess which health issues are most critical for a selected group of people.

One of the largest subfields of demography in public health concerns fertility and family planning. In many of the world's most developed economies, the overall birth rate is high enough to support stable growth without posing unusual challenges to a country's public resources, such as healthcare. However, many developing economies are experiencing rapid population growth. Demographers studying these trends are likely to be involved with health issues concerning mothers and children. The Demographic and Health Surveys (DHS) and the Multiple Indicator Cluster Surveys (MICS) are often implemented in these environments. The United Nations Children's Fund implemented the MICS in more than 120 developing nations in the first twenty years of the twenty-first century to inform such issues. Demographers in this area of research may also be employed by government agencies as advisers on the development of public policies shaping long-term population growth, such as economic incentives for having more or fewer offspring.

Immigration and Emigration Policy. Demographers advising on immigration and emigration policy examine issues such as how much of a country's population growth is caused by people moving into the country and why a country's most educated residents are leaving for other countries. Although questions of migration are important in a wide range of contexts, public policy is developed by government agencies and specialized research firms, where demographers focusing on the issues are most likely to work. Migration policy has become a topic of great public interest in the twenty-first century in areas such as the European Union, where residents may live and work not only in the country of which they are a citizen but also in member countries. Regions such as the Caribbean and countries formerly part of the Soviet Union are studying emigration to better understand how to retain their most skilled citizens, who have moved in large numbers to countries with stronger economies in a trend known as brain drain.

Urban and Environmental Planning. Population change has a profound effect on the environment, especially where housing and employment are concerned. As people live and work in an area, they influence its natural resources and the types of infrastructure needed to sustain further growth, such as houses, roads, schools, stores, and offices. Demographers who work in the field of urban and environmental planning hold a variety of jobs. They may work for city planning agencies or provide research for national offices such as the US Department of Housing and Urban Development. They also may specialize in specific categories of growth, such as families with young children, to advise boards and departments of education in planning school systems. Many demographers choose to work in private industry for companies such as homebuilders, where they support the design of new types of houses or make forecasts about where and when population growth is likely to be highest.

Careers and Course Work

Demographers have a wide range of career options in government, industry, and nonprofit settings. Because there is no association that certifies college and university programs in demography, few numbers are available when it comes to students or full-time employees in the field. However, the professional demands of studying population change make a bachelor's degree or graduate degree an asset when looking for a job.

Students interested in demography—also known as population studies at many institutions—are likely to approach it as a topic within a major in sociology, anthropology, political science, economics, geography, or biology. Coursework varies widely, depending on the student's focus and department. Most students interested in demography take classes on topics such as population theory and human development. Multiple courses on research methods, study design, and statistical analysis are required. Issue-specific classes cover topics such as poverty, reproductive policy and health, and the environmental impact of human populations. Students who earn graduate degrees often take managerial positions or work as professors or researchers at academic institutions.

Government agencies and nonprofit organizations employ many demographers. The US Census Bureau is one of the best-known agencies, but population studies play a key role in aspects of government ranging from healthcare policy to land use. In industry, jobs in marketing and new product development often call for experience in gathering and interpreting demographic data. This experience can come through college-level coursework as well as internships with consumer products manufacturers.

Social Context and Future Prospects

The demand for professionals with a background in demography and population studies is expected to remain steady through the early twenty-first century. Job candidates with bachelor's or graduate degrees and years of focused experience in demographic analysis are likely to benefit most. There will also be many opportunities for new college graduates with coursework in demography.

The US Bureau of Labor Statistics (BLS) reports that sociologists, a group to which many demographers belong, will see a small projected growth of about 5 percent in job outlook from 2020 to 2030. Survey researchers, another BLS category that includes many demographers, are expected to have slower-than-average growth over that same period. This is partly due to advances in data collection methods. For example, information is increasingly collected from social media sites, which decreases the need for traditional survey methods, thus reducing the number of survey researchers needed. Many opportunities open to demographic specialists are not called "demographers" but carry titles like "policy analyst" or "research analyst."

Government agencies will continue to hire demographers as elected officials look for more efficient ways to use tax funds. Demographers can help evaluate whether a particular program is effectively reaching its target audience. Consumer products manufacturers and marketing firms will hire more demographic specialists as new product development and advertising focus on smaller customer niches. Research centers and management consulting firms will likely be interested in demographers for their experience working with complex data on population change.

Climate change and the socioeconomic development of human populations are primary concerns in demography and demographics in the twenty-first century. Sponsored by the Wittgenstein Centre for Demography and Global Human Capital, the Shared Socioeconomic Pathways (SSP) framework investigates human populations regarding sex ratio, life expectancy, migration, education, and more. Understanding and predicting the likely population makeup of various countries is increasingly important in creating sustainable solutions and advising the global scientific community.

Bibliography

Buchholz, Todd G., and Martin Feldstein. “Malthus: Prophet of Doom and Population Boom.” New Ideas from Dead Economists: An Introduction to Modern Economic Thought. Penguin, 2007.

Hayes, Adam. "Demographics: How to Collect, Analyze, and Use Demographic Data." Investopedia, 26 Feb. 2024, www.investopedia.com/terms/d/demographics.asp. Accessed 20 June 2024.

Luo, Weijie. Inequality, Demography and Fiscal Policy. Springer, 2023.

Magnus, George. The Age of Aging: How Demographics Are Changing the Global Economy and Our World. Wiley, 2008.

Malthus, Thomas. An Essay on the Principle of Population. Oxford UP, 2008.

Poston, Dudley L., Jr., and Leon F. Bouvier. Population and Society: An Introduction to Demography. 2nd ed., Cambridge UP, 2018.

Roy, Amlan. Demographics Unravelled How Demographics Affect and Influence Every Aspect of Economics, Finance and Policy. Wiley, 2022.

Schmidt, Chloe, et al. "Genetic and Species-Level Biodiversity Patterns Are Linked by Demography and Ecological Opportunity." Evolution, vol. 76, no. 1, 2022, pp. 86–100. doi:10.1111/evo.14407. Accessed 1 Mar. 2022.

Siegel, Jacob S., and David A. Swanson, eds. The Methods and Materials of Demography. 2nd ed., Elsevier, 2004.

"Survey Researchers." US Bureau of Labor Statistics, 17 Apr. 2024, www.bls.gov/ooh/life-physical-and-social-science/survey-researchers.htm#tab-1. Accessed 20 June 2024.

Yaukey, David, Douglas L. Anderton, and Jennifer Hickes Lundquist. Demography: The Study of Human Population. 4th ed. Waveland, 2015.