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Explainer

The 2020 Census Population and Apportionment Data, Explained

The numbers determine representation in Congress for the next 10 years.

On Monday, the Commerce Depart­ment and the Census Bureau released the first results of the 2020 Census, the consti­tu­tion­ally required, once-a-decade effort to count every person resid­ing in the United States. Monday’s data release showed a total of seven congres­sional seats shift­ing among 13 states, with the gains made by states in the South and West.

These results arrive after years of plan­ning to ensure a full, fair, and accur­ate count, as well as years of fights against threats to those plans, from under­fund­ing to unpre­ced­en­ted polit­ical inter­fer­ence from the Trump admin­is­tra­tion. And states will soon receive the numbers they need to redraw polit­ical maps, along with many other data sets.

Why is the census import­ant?

The census is about polit­ical power and money. Census results are used to alloc­ate seats in the U.S. House of Repres­ent­at­ives among the states. Simil­arly, states and local­it­ies use census data to redraw the bound­ar­ies of their congres­sional and other legis­lat­ive districts. Census data also determ­ines the distri­bu­tion of over $1.5 tril­lion dollars annu­ally in federal funds for much-needed programs like health­care, food assist­ance, and educa­tion.

The stakes of this decade’s census are espe­cially high for communit­ies of color. The nation’s popu­la­tion growth over the past 10 years came entirely from nonwhite communit­ies, and Latino, Black, and Asian Amer­ican voters will collect­ively account for 80 percent of the increase in eligible voters between 2010 and 2020. For communit­ies of color to receive polit­ical repres­ent­a­tion and crit­ical invest­ments commen­sur­ate with their size, they must be coun­ted fully. The census, however, has histor­ic­ally failed to do so, strug­gling partic­u­larly to count Black, Latino, and Native Amer­ican communit­ies as accur­ately as it has white communit­ies. These chronic under­counts have contrib­uted to entrenched inequal­ity.

What numbers were released Monday?

The Census Bureau released two sets of state popu­la­tion totals, as well as the number of seats each state will have in Congress for the next 10 years. The first data set shows the “resid­ent popu­la­tion” of the 50 states, the District of Columbia, and Puerto Rico, as of Census Day, which was April 1, 2020. The second set — the appor­tion­ment counts — is the one the federal govern­ment uses to divide the 435 seats in the House among the states. The appor­tion­ment counts include all persons resid­ing in the 50 states as of Census Day. In the 2020 Census, the appor­tion­ment popu­la­tion also includes U.S. Armed Forces person­nel and federal civil­ian employ­ees stationed outside the United States, as well as their depend­ents living with them. The bureau has alloc­ated them to their home states.

Both these data­sets are solely head­counts at the state and national levels. None of the data released Monday reveals any demo­graphic inform­a­tion such as age, race, or ethni­city.

Monday’s announce­ment also included the number of congres­sional seats for each state, which will take effect for the 2022 elec­tions. Six states gained seats — Color­ado, Flor­ida, Montana, North Caro­lina, Oregon, and Texas — while seven other states lost seats — Cali­for­nia, Illinois, Michigan, New York, Ohio, Pennsylvania, and West Virginia.

The Commerce Depart­ment and the bureau arrived at these numbers by feed­ing the appor­tion­ment counts into a math­em­at­ical formula set by law. This formula ensures that every state gets one seat and, after that, states with more people get more seats than states with fewer people. While states now know how many congres­sional districts they must draw, they will need to wait longer for more gran­u­lar popu­la­tion data before they can set new bound­ar­ies for this decade’s elec­tions.

What happens next with the numbers?

The secret­ary of commerce has put the appor­tion­ment process into motion. Federal law sets the steps. Commerce Secret­ary Gina Raimondo delivered the popu­la­tion totals and congres­sional seat appor­tion­ments to Pres­id­ent Biden on April 26. He must now trans­mit the popu­la­tion totals and seat appor­tion­ment to Congress, which will send the governors of each state certi­fic­ates show­ing them how many seats their state will have going forward.

In the past, haven’t appor­tion­ment numbers come out earlier?

The numbers have come out faster before, but for the 2020 Census, accur­acy is more import­ant than speed. The Census Bureau has histor­ic­ally released appor­tion­ment numbers before Decem­ber 31 the year the census is taken, in accord­ance with a federal stat­utory dead­line. But last year, the Covid-19 pandemic hit the United States just as the 2020 Census was getting under­way. The bureau consequently announced that it needed to extend many of its oper­a­tions by several months, includ­ing knock­ing on doors of house­holds that did not self-respond to the census and processing the data it collec­ted. This second step, data processing, is crucial for help­ing safe­guard the accur­acy of census data and redu­cing the inequal­it­ies that have histor­ic­ally resul­ted when the census has under­coun­ted communit­ies like young chil­dren and people of color.

Advoc­ates fought hard to ensure that the census would not be rushed. Despite the bureau’s conclu­sion that it needed more time to cope with the pandemic, the Trump admin­is­tra­tion last summer tried to speed up the entire census process so that the former pres­id­ent could try to carry out an uncon­sti­tu­tional direct­ive to exclude undoc­u­mented persons from the appor­tion­ment count. A lawsuit, National Urban League v. Ross, resul­ted in a judi­cial order requir­ing the bureau to keep count­ing. Subsequently, the Trump admin­is­tra­tion aban­doned its plans to rush data processing and manip­u­late the census data using citizen­ship data. The result of these fights has been an appor­tion­ment sched­ule close to the one the bureau had origin­ally set for itself last year to respond to Covid-19.

Are these the only numbers we’ll see from the 2020 Census?

No, more data releases are yet to come. In the upcom­ing months and years, the bureau will produce addi­tional data sets that will be cent­ral to social science research, busi­ness decision-making, and myriad other uses. Partic­u­larly signi­fic­ant among these pending releases, however, is the data set for redis­trict­ing, the process whereby states and local govern­ments redraw the lines for their elect­oral districts for Congress, state legis­latures, and other polit­ical bodies. This redis­trict­ing data set will include popu­la­tion counts and demo­graphic inform­a­tion such as race and ethni­city down to the “census block” level, so it is much more detailed than the appor­tion­ment data. (The bureau does not release inform­a­tion that iden­ti­fies specific indi­vidu­als, in keep­ing with legal confid­en­ti­al­ity protec­tions to keep every­one’s data safe.)

As with the appor­tion­ment data, the Census Bureau announced that it needs more time to produce accur­ate redis­trict­ing files. It plans to trans­mit that data by Septem­ber 30, 2021, and will release it in a less processed form by mid-August. Some states have chal­lenged this exten­sion of time in court. But, given the unpre­ced­en­ted condi­tions under which the Census Bureau had to enumer­ate the popu­la­tion in 2020, it needs time to produce data that will be fit for use.

What can states do to prepare for the release of census redis­trict­ing data?

A lot. The gran­u­lar redis­trict­ing data needed to redraw maps will not be avail­able until August or Septem­ber, but despite the later than normal data release, there is much that states can begin to do now, like hold­ing hear­ings to gather public input. States may also want to consider releas­ing prelim­in­ary maps for public comment using data from the Amer­ican Community Survey, with the import­ant caveat that this data will be much less precise than actual census data and should­n’t be used to draw final maps.

Start­ing the work of public engage­ment while wait­ing for data will help states produce maps on time once the neces­sary data is published. Crowd­sourcing inform­a­tion to identify communit­ies of interest, which share common repres­ent­a­tional needs, also will inform map draw­ers of factors that may not be appar­ent in popu­la­tion data. Such input is indis­pens­able for fair districts because it makes community needs a focal point for mapping decisions.

States may also want to consider whether filing dead­lines or even primary dates for 2022 should be pushed back to give map draw­ers more time to run a robust redis­trict­ing process given that block-level data will come out later than normal this year.

What factors have shaped the 2020 Census count?

The 2020 Census has faced myriad chal­lenges. The pandemic, hurricanes, and wild­fires displaced people through­out the coun­try and made canvassing door-to-door harder. Mean­while, the Trump admin­is­tra­tion sought to add a citizen­ship ques­tion to the census form — which experts predicted would deter millions of people from complet­ing it — and attemp­ted to rush the count at the last minute to exclude undoc­u­mented people.

But other devel­op­ments helped bolster the count. The Supreme Court blocked the citizen­ship ques­tion. Advoc­ates preven­ted the Trump admin­is­tra­tion from skip­ping essen­tial count­ing time, obtained an enforce­able prom­ise from the federal govern­ment that undoc­u­mented persons will be coun­ted in the 2020 Census (as they always have been), and won crucial time for the bureau to process and spot errors in the data. And nonprofits and state and local govern­ments worked tire­lessly for years to encour­age full parti­cip­a­tion in the census.

How accur­ate is the 2020 Census?

It’s too soon to say. The congres­sional seat alloc­a­tions released on Monday tracked — but did not exactly match — projec­tions from lead­ing demo­graph­ers and census experts, with slightly fewer seats chan­ging hands among states than predicted. But that’s just one data point for analyz­ing the census’s over­all qual­ity, not the whole story by any means.

For starters, the qual­ity of census data depends on how the numbers will be used. For example, the data might get each state’s relat­ive share of the national popu­la­tion right — the only thing that matters for appor­tion­ment — but get the actual head counts in some, many, or even all states wrong. That could result in states and local­it­ies losing valu­able federal funds down the line.

Or the appor­tion­ment totals could cover up racial or ethnic differ­en­tial under­counts, which occurred in 2010. If severe differ­en­tial under­counts happen this decade, that could damage the data’s useful­ness for redis­trict­ing, in which accur­ate racial and ethnic data is neces­sary to keep communit­ies of interest together and comply with the Voting Rights Act. And it may also leave under­coun­ted communit­ies short of federal funds.

Of course, some import­ant clues about census qual­ity already exist. In Decem­ber, the bureau released national popu­la­tion estim­ates based on birth, death, migra­tion, and other govern­ment records that provide the first rough bench­mark for coun­try-level counts. The national popu­la­tion number released on Monday — 331,449,281 — falls within the bureau’s estim­ates, about roughly between its low estim­ate (330,730,000) and its middle one (332,601,000). And experts have also been analyz­ing self-response patterns around the coun­try, which might flag places where under­counts are more likely to have occurred.

But there are many other pieces to the puzzle that will only click into place over the next year. Most import­ant will be the bureau’s Post-Enumer­a­tion Survey (PES), which, among other things, will help the bureau identify under­counts of any specific racial or ethnic group. The 2020 PES data will not be avail­able in full until spring 2022. The bureau and the Amer­ican Stat­ist­ical Asso­ci­ation will produce more qual­ity metrics in the interim. And the redis­trict­ing data sets will arrive by Septem­ber. Experts will analyze all these data sources together to get a fuller sense of how well the Census Bureau did this decade.