This report provides a 100-year look at the impact of immigration on the nation’s demographics since passage of the 1965 Immigration and Nationality Act. It explores how the nation’s population has changed since the law was enacted and includes new Pew Research Center population projections through 2065. These projections are included for the nation as a whole as well for its immigrant generations and its racial and ethnic groups. The new projections are based on detailed assumptions about births, deaths and immigration levels—the three key components of population change. All these assumptions are built on recent trends, but it is important to note that these trends can change. As a result, all population projections have inherent uncertainties, especially for years further in the future, since they can be affected by changes in behavior, new immigration policies or other events.

The projections and historical population estimates that are the focus of Chapter 2 of this report are adjusted for undercount in the census data in order to ensure consistency over time and with estimates of immigrants by legal status (Passel and Cohn 2015). Accordingly, the projections and estimates are not consistent with Census Bureau data about the number and characteristics of immigrants analyzed in Chapters 3 and 5 of this report, and the two sets of numbers may differ. For more, see Appendix A: Methodology (link).

New survey findings from the Pew Research Center’s American Trends Panel exploring the U.S. public’s views of immigrants and their impact nationally and in local communities are also included in this report. The survey was conducted in English and Spanish online among a nationally representative probability sample from March 10 to April 6, 2015, before the current national discussion about national immigration policy, unauthorized immigration and birthright citizenship. The survey’s margin of sampling error is plus or minus 2.4 percentage points at the 95% confidence interval.

The report also examines the economic and demographic characteristics of immigrants in the U.S. today as well as trends in the characteristics of immigrants who have arrived since the 1960s. The data for this portion of the report and the accompanying statistical portrait (link) of the nation’s foreign-born population in 2013 come from several sources, including the U.S. Census Bureau’s 2013, 2010 and 2007 American Community Surveys, which provide detailed geographic, demographic and economic characteristics of the nation’s immigrant population, and the 1960, 1970, 1980, 1990 and 2000 decennial censuses (IPUMS).

Accompanying the report are two interactives. The first is a legislative timeline (link) highlighting key U.S. immigration policy legislation and executive actions since 1790. The second is an interactive map showing (link), at the state level, the largest immigrant group in each state from 1850 through 2013.

Many people contributed to the writing and development of this report. Richard Fry, senior researcher, was the primary project leader and wrote Chapter 3. Mark Hugo Lopez, director of Hispanic research, and D’Vera Cohn, senior writer/editor, wrote the overview. Lopez also provided editorial guidance on all aspects of the report. Chapter 1 was written by Cohn. Chapter 2 was written by Cohn and Jeffrey S. Passel, senior demographer. Chapters 4 and 5 were written by Anna Brown, research assistant, who also compiled the statistical portrait of immigrants (link).

Editorial guidance was provided by Claudia Deane, vice president, research; Kim Parker, director of social trends research; Juliana Menasce Horowitz, associate director of social trends research; and Paul Taylor, former executive vice president of the Pew Research Center. Brown and Horowitz managed development of the survey questionnaire; research methodologists Kyley McGeeney and Andrew Mercer provided guidance on questionnaire development and survey implementation. Gustavo López, research assistant, and Renee Stepler, research assistant, created charts and tables for various parts of the report. Stepler also compiled the immigration law timeline. Michael Keegan, information graphics designer; Michael Suh, associate digital producer; and Dana Amihere, Web developer, provided digital support for the report and its accompanying interactives. Eileen Patten, research analyst, number-checked the graphics and text, as did Brown, López and Stepler. Marcia Kramer copy edited the report.

Find related reports online at pewresearch.org/hispanic and pewresearch.org/social-trends.