A beginner’s guide to census data

Dana Amihere
Engagement at LAist
8 min readNov 18, 2019


When it comes to engaging those most at risk of an undercount in the 2020 Census, mainstream media faces many of the same challenges as the U.S. Census Bureau. In many communities — especially communities of color and immigrant, non-English-speaking communities — we are not recognizable news sources and therefore not trusted messengers.

Two years ahead of the 2020 count, KPCC-LAist identified the census as a major story. Congressional representation is at stake, along with $800 billion in federal funds that will get disbursed for state, county and community programs over the next decade. It’s an especially big deal in Los Angeles, which is considered the hardest-to-count county in the country.

That’s why we set out to better understand the census information needs and habits of Angelenos most at risk of an undercount using a human-centered design research approach. That process also helped us better understand who the most trusted messengers are.

“Outside the Box” human-centered design census research report
(Download the full report)

Among them are the journalists and 100-plus media outlets embedded within these communities, especially those who publish content in their audiences’ native languages and address issues most impactful to their communities.

From day one, KPCC-LAist’s goal has been to make sure that residents across Southern California know about the importance of the U.S. Census and the implications of an undercount. As our awareness of the obstacles has sharpened, we’ve realized a meaningful collaboration with community, ethnic, and in-language media is the only way to accomplish this goal. (Interested in participating in the collaboration? Email my colleague Ashley Alvarado.)

In May, we held a lunch with area in-language ethnic media outlets. Many people shared how they hadn’t reported on the census because they didn’t feel comfortable working with its data. They expressed a desire for training around census data. On Nov. 8, we hosted a dozen ethnic media professionals at KPCC to do just this.

Dana Amihere leads a census data training session for professionals from about a dozen in-language, ethnic media outlets on Nov. 8. (Photos: Quincy Surasmith/KPCC)

The concept was simple: We wanted to help our partners, who have extensive reach into the communities who have been identified as the hardest to count, better understand census data and use it to enrich their reporting.

We sent out a survey prior to the training asking what the journalists would find most helpful. Based on the responses we received, we tailored the first part of the training to address their needs. We focused on how to navigate the new data.census.gov website to find information on different racial and ethnic groups. The second part of the training answered specific questions related to their reporting and made connections to tie census and American Community Survey data to available data about hard-to-count communities in Los Angeles County (the nation’s hardest-to-count county) and across California.

Here are some helpful tips and information based on that training to help you start using census data.

Let’s start with the basics.

Where do I find census data?

Data.census.gov is the new platform to access data and digital content from the U.S. Census Bureau. The idea with this new release, which will replace American FactFinder entirely by the end of 2019, was to improve user experience. Now, census data is available in one centralized place rather than scattered across several applications and programs with different websites and entry points.

New census data platform, data.census.gov (U.S. Census Bureau)

What’s at stake in participating in Census 2020?

At its core, the simplest explanation is money and power.

- Federal funding

In fiscal year 2015, $590 billion was distributed to 16 large federal financial assistance programs using census data. This funding supports programs like Head Start, food stamps, foster care and adoption services and Section 8 housing vouchers.

- Representation

A complete count of who lives where through the decennial census gives the government the information needed to draw Congressional districts (which are supposed to have approximately the same number of people) and determine how many seats each state should be apportioned in the House of Representatives (there are always 435 seats but they may be divvied up differently depending on which areas have lost or gained residents since the last census). Census data also helps states and local entities redistrict to determine proper representation for residents.

- Good data

Census data gets used all the time, for numerous reasons by countless individuals for research, urban planning, and news gathering. However, everyone who uses the data to analyze a community relies upon its accuracy. Good data can only result from a complete and accurate census enumeration every 10 years.

How does the decennial census count differ from ACS data?

The decennial census enumeration is conducted every 10 years across the country to capture the total number of residents. The data, however, isn’t immediately available. For example, data from the 2020 Census won’t be widely released until after the U.S. Census Bureau delivers redistricting counts to the states in March 2021.

The ACS, or American Community Survey, is a dataset released every year with a more detailed look at the social and economic conditions of communities across the country. It asks questions about education, housing, jobs and more. Although the ACS represents data for the entire United States, only 3.5 million households are selected to participate each year. Like the decennial census, you are legally required to respond to the ACS if you receive a survey. Additionally, just like the data you provide on your census form, your ACS data is aggregated (meaning no one can pick out your particular answers), confidential and protected by law.

American Community Survey 2019 form
American Community Survey 2019 form. (U.S. Census Bureau)


Understanding how the U.S. Census Bureau uses geographies, some of which were created by the agency but are used often by others, is key to understanding census data.

According to the Census Bureau:

Geography is at the center of taking a census. We do not just count people; we count people where they live. Geography is important because it is the basis for taking a census and for tabulating census data. The Census Bureau also maintains unique geographic areas that other local, state and federal agencies use.

The nation is subdivided into two main types of geographic areas: legal and statistical.

Legal areas are defined specifically by law, and include state, local and tribal government units, as well as some specially defined administrative areas like congressional districts. Many, but not all, are represented by elected officials.

Example: New York State

Statistical areas are defined directly by the U.S. Census Bureau and state, regional, or local authorities, and include census tracts and urban areas. The primary purpose of statistical areas are to tabulate and present census data.

Example: Metropolitan Statistical area — “Boston-Cambridge-Quincy-MA-NH Metro area”

Census geographies are hierarchical and inter-relational. For example, census blocks make up block groups and block groups compose census tracts. Census tracts fall within county boundaries, and counties are how states are divided.

Hierarchy of census geographies chart
(U.S. Census Bureau)

Certain types of geographies are better equipped to answer certain data questions about an area.

If you want to talk about…

…A region like the Greater Los Angeles metro area, use an MSA (Metropolitan Statistical Area).

…A regional area like the San Fernando Valley or South Antelope Valley, look for it described as a CCD (Census County Division) or County Subdivision.

…A neighborhood like Koreatown, use PUMAs.

…A specific part of a neighborhood or small area, try using census tracts or block groups.

MSAs? PUMAs? You might be wondering what some of these terms mean. Census Reporter has a great glossary of census geographic terms that can help you decode the many abbreviations and designations within the census data universe.

Some of the most commonly used census geographic terms, though, are:

CDPs = Census Designated Places (aka Places)

CDPs have no legal status or government, but they are identifiable by name. The boundaries of CDPs are usually defined in cooperation with local officials, and are subject to revision at each decennial census.

FIPS = Federal Information Processing Standard (aka FIPS codes)

To identify a geographic area in larger contexts like the nation, one or more higher level geocodes may be required. Census tracts are unique within counties and counties are unique within states. You need the full set of state, county, and tract geocodes to uniquely identify a census tract.

Example: The unique geocode for the census tract 201 in Autauga County, Alabama is 01001020100.

FIPS code example for census tract 201 in Autauga County, Alabama
This is how the FIPS code for census tract 201 in Autauga County, Alabama is decoded.

MSAs = Metropolitan Statistical Areas

An MSA is a county or counties around an urban core of population greater than 50,000.

PUMAs = Public Use Microdata Areas (aka census microdata)

PUMAs are geographic units used by the U.S. Census Bureau for providing statistical and demographic information. Each PUMA contains at least 100,000 people. PUMAs do not overlap, and are contained within a single state.

ZCTAs = ZIP Code Tabulation Areas

ZCTAs are generalized areal representations of U.S. Postal Service (USPS) ZIP Code service areas. The USPS ZIP Codes identify the individual post office or metropolitan area delivery station associated with mailing addresses.

More definitions and terms from Census Reporter >>

Speaking of Census Reporter, it’s a fabulous resource for the newbie to census data or if you’re more experienced and just looking for a census data point quickly. While great strides have been made as far as the user experience on the new data.census.gov website, Census Reporter is a fast, user-friendly shortcut.

Los Angeles city Census Reporter profile page. (Census Reporter)


The U.S. Census Bureau has produced a series of video tutorials to help users learn to navigate the new census data platform, data.census.gov, with ease. Here are three videos to help you get started with basic searches for race and ethnicity information.

How to access race data

Discover how to find population totals and characteristics across race groups using the advanced search on data.census.gov.

. . .

How to access an American Community Survey profile about your community

Learn an easy way to access social, economic, housing, and demographic statistics for your selected area or multiple areas on data.census.gov.

. . .

How to access information about the Hispanic population

Looking for Census Bureau data on the Hispanic population? Learn tricks to easily access this information using data.census.gov.


Census Reporter

Census Academy

California Hard-to-Count Map

Mapping U.S. Hard-to-Count Communities

Download the handouts we provided at our in-person training in English or Spanish.



Dana Amihere
Engagement at LAist

Data Editor at Southern California Public Radio (KPCC + LAist) | Twitter: @write_this_way