What are population demographics?

The population of a country refers to those individuals who live in it, known as residents. It also includes residents temporarily outside the country, such as those in the armed forces, diplomats or astronauts. Each of these people have unique characteristics, such as gender, race, ethnicity, income level and education level attained. This map explores ethnicity.

Ethnicity is often used interchangeably with race, but the two are distinct. The concept of race was developed during the 1600s to justify the enslavement of Black people. In the United States, being “Black” meant having any Black ancestor, regardless of how distant the relation. The term “white” was originally reserved only for people of Anglo-Saxon descent, though it has since been expanded to include people with European ancestry. Race was used to differentiate people in a system that afforded white people political, social and economic privileges. Ethnicity, on the other hand, describes a person's cultural identity, which can relate to their nation of origin, history or customs. Both race and ethnicity are social constructs that people use to classify each other; neither has a biological foundation. In the United States, racial and gender discrimination typically occurs based on intersecting considerations of race, ethnicity and gender.

The United States has a long history of discrimination based on race and ethnicity, and discriminatory practices are often built into the very structure of society. Still there are ways that people can, and do, combat discrimination. Learn how to disrupt discrimination when you see it from groups like Right To Be, The Conscious Kid, Color of Change or the ACLU. You can also learn more from programs like Code Switch.

Both race and ethnicity can be identified by others, but we can also define our own race and ethnicity. The two are not always the same. When the U.S. Census was established, it was up to census-takers to determine a person’s ethnicity. Later, people selected their own race and ethnicity, though they could choose just one option for each. This is significant because the government uses the census data to make funding decisions. Since funding depends on population counts, groups are underfunded when they are undercounted.

At the same time, individuals or groups may reject the categories that the U.S. government offers. For example, some indigenous people of North America reject the term “Indian” and prefer to be called by their specific tribal affiliation. It is important for those outside of a community (whether related to race, ethnicity or another social construct) to find out from those within it what term they prefer to be called.

The data featured in this map layer is from the United States Census Bureau from data collected in the 2010 Census. All race and ethnicity data is self-reported by the individual completing the survey.

Why collect population demographics?

Governments at all levels use demographic data to create or adjust policies and programs they implement. That same data can also provide those governments, or those monitoring them, with a tool to evaluate those policies and programs to ensure they are serving people equitably or monitor the effectiveness of anti-discrimination policies. Additionally, just like we look at data geographically, when we sort data by factors like gender, ethnicity, race or disability, we can evaluate it to identify issues impacting one group more severely than others.

What are census tracts?

The data in this map layer has been mapped using census tracts instead of counties or states. According to the U.S. Census Bureau, census tracts are “small, relatively permanent statistical subdivisions of a county or equivalent entity that are updated by local participants prior to each decennial census.” Census tracts strive to cover the area where 4,000 people live, though they can range from approximately 1,200-8,000 people depending on population density. People living on an American Indian reservations may have census tracts different from non-reservation systems. Census tracts in reservations sometimes cross boundaries, such as county lines, that other census tracts are restricted from doing.

What is predominance mapping?

This map layer has been classified using a technique called predominance mapping. This method creates a map that compares multiple variables in the data and then displays the most common or highest value. In this case, we’ve mapped self-selected ethnicity data from the U.S. Census Bureau with this technique. This displays the most commonly reported ethnicity of each census tract. Some tracts are very close between two ethnicities, these have a lighter shade than those with a clear leader.

It is important to note that this map illustrates ethnicity data collected by the U.S. Census, but it does not enable a comprehensive understanding of how mixed-race individuals and communities create unique touchstones and contribute to the rich culture of the United States. National Geographic Explorer Clinton Johnson strives to advance social justice and equity through GIS mapping technology. Johnson is co-founder and executive director of NorthStar of GIS, a 501(c)(3) non-profit committed to creating a more racially-just world through more racially-just GIS, geography and STEM fields.