Foreign-Born Share Would Hit Historic High in Seven Years Under S.744

One in Seven U.S. Residents Would Be Immigrants by 2020

By Steven A. Camarota on June 23, 2013

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Steven A. Camarota is the Director of Research at the Center for Immigration Studies.

According the Congressional Budget Office (CBO), the Gang of Eight Bill (S.744) would dramatically increase legal immigration while reducing future illegal immigration by only 25 percent. Based on CBO's numbers, the Center for Immigration Studies projects that under S.744 the foreign-born (legal and illegal) share of the U.S. population would hit a record high of 15 percent in 2020 — surpassing the all-time high of 14.8 percent reached in 1890. Based on CBO's analysis, we further project that the foreign-born would reach 17 percent of the population by 2033, a level never before seen in U.S. history. The total size of the foreign-born population would grow to 55.9 million by 2023 and nearly 65.2 million by 2033 if S.744 becomes law. To place this into perspective, the foreign-born population was less than 20 million as recently as 1990 — 7.9 percent of the total population.


  • The record high of 15 percent projected for 2020 if the bill passes means that over just a 50-year period the foreign-born share of the population would have more than tripled, from 4.7 percent in 1970. There has never been a period in American history when the foreign-born share grew this fast.
  • The size of foreign-born population doubled from 1990 to 2010, nearly tripled since 1980, and quadrupled since 1970. If S.744 becomes law it would quintuple by 2020, compared to 1970.
  • The size of the foreign-born population will have increased from 9.6 million in 1970 to 31.1 million in 2000, to 65.2 million by 2033.
  • Based on the CBO projections, the total size of the U.S. population will reach 351.8 million in 2023, an increase of 43.1 million compared to 2010. It will reach 381.5 million by 2033, a 72.8 million increase over the 2010 Census.
  • Despite all this increase in the U.S. population, S.744 would have almost no impact on slowing the aging of American society. With or without S.744, 57 percent of the U.S. population will be of working age (18-64) in 2030.
  • It is worth pointing out that the size and share of the foreign-born population and the share would not stabilize in 2033 under S.744. Both would continue to increase significantly after that date.


There has been a lot of discussion about the impact of S.744 on public coffers and some discussion of the labor market. But there has been very little debate on how the bill would impact the size of the nation's foreign-born population or the nation's overall population. It must be remembered that immigration plus natural population increase was already going to increase the size of the U.S. population from 308.7 million in 2010 to 358.5 million in 2030 and 399.8 in 2050 according the Census Bureau.1 The Gang of Eight's immigration bill would add significantly to these totals. What is the absorption capacity of America's roads, bridges, schools, and power grid? How does increasing the size of the population impact the quality of life in the United States? Does the size of the foreign-born population impact how immigrants integrate and assimilate into American society? These and other questions would seem to be very important, but have barely been mentioned in the current debate.

Immigration and Aging. One argument that is often made for S.744 is that it will offset the aging of American Society. However, there is no meaningful impact. The Census Bureau middle-range population projections show that 57 percent of the population will be of working age (18-65) by 2030.2 If S.744 becomes law and the immigration increases contained in the bill go into effect, we project that 57 percent of the population would be of working age in 2030. Thus, despite a dramatic increase in immigration levels, the working-age share under S.744 would remain essentially the same.

Demographers have long known that immigration has only a small impact in slowing the aging of developed, low-fertility societies such as our own. As noted in an important 1992 article in Demography, the leading academic journal in the field, "constant inflows of immigrants, even at relatively young ages, do not necessarily rejuvenate low-fertility populations. In fact, immigration may even contribute to population aging."3 The Census Bureau concluded in projections done in 2000 that immigration is a "highly inefficient" means for increasing the percentage of the population that is of working-age in the long run.4 We can also see how small the impact of immigration is from the Bureau's latest population projections. The Bureau's high-immigration projection shows 57.5 percent of the population will be of working age (18 to 64) in 2030, compared to 57.3 percent under the Bureau's middle-range projection.5 Immigrants age like everyone else and their fertility is not that much higher than that of the native-born population. While immigration can make the overall population much larger, it does not significantly increase the share of the population that is of working age.


We rely on a straightforward methodology to generate these projections. The Congressional Budget Office's cost estimate of S.744 states that been if S.744 becomes law the U.S. population will be 10.4 million larger in 2023 than it otherwise would be. CBO also projects that it will be 16.2 million larger in 2033 if the bill becomes law.6 We simply adjust upward the Census Bureau's net immigration assumptions from its newest middle-range projections to create a population that is larger in 2023 and 2033 by the amounts that CBO estimates. To create these projections we first match Census Bureau population. The projection model that replicates Census Bureau projections was developed by the Center for Immigration Studies and Arlington, Va.-based Decision Demographics. A paper based on this model was first presented at the Population Association of America in 2012.7

The Census Bureau middle series population projections show a total U.S. population of 341.4 million in 2023 and 365.3 million in 2033.8 This represents a significant increase in the U.S. population from 308.7 million in 2010. The Congressional Budget Office projects that under S.744 there would be an additional 10.4 million U.S. residents in 2023 and 16.2 million additional residents in 2033.9 These additional residents are on top of the increase that would have taken place from natural population increase and immigration under existing law. It should be noted that the number of additional residents that would come from S.744 are not all immigrants. It would include children born in the United States to the additional immigrants that come because of S.744. Our model incorporates this fact.

If we combine CBO projections with the Census Bureau's, the U.S. population would be 351.8 million in 2023 (341.4 million plus 10.4 million) and 381.5 million in 2023 (365.3 million plus 16.2 million). We then adjust up Census Bureau estimates of net immigration so that the population totals match what CBO foresees under S.744. Net immigration is the combined total of new arrivals minus departures. The Census Bureau had estimated net immigration of 794,000 a year in 2015 rising to 978,000 by 2023 and 1.15 million by 2033.10 To add an additional 10.4 million residents (additional net immigrants plus births, minus deaths) we adjust upward Census Bureau net immigration to 1.6 million in 2015 and two million in 2023. This produces a total U.S. population in 2023 that is 351.8 million — 10.4 million larger than under the Bureau's middle-range projections.

The CBO projects that immigration falls after 2023, though the level will still be a good deal higher than the projections the Census Bureau issued in 2012. To reach 381.5 million by 2033, net immigration would rise in the decade after 2023 from 1.3 million a year in 2024 to 1.5 million by 2033. This produces a total U.S. population of 381.5 million in 2033 — 16.2 million larger than the Census Bureau projected.11 Table 1 at the end of this analysis reports net immigration under Census Bureau assumptions and under adjustment of those levels to match CBO projections. It also reports the size of the total population and the foreign-born population.







End Notes

1 Table 1 middle series shows the size of the U.S. population through 2060 under the Bureau's middle-range immigration assumptions.

2 Table 3 middle series shows the working-age (16-64) share of the population through 2060 under the Bureau's middle-range immigration assumptions.

3 Carl P. Schmertmann, "Immigrants' Ages and the Structure of Stationary Populations with Below-Replacement Fertility", Demography (Vol. 29, No. 4), 1992.

4 See F.W. Hollmann, T.J. Mulder, and J.E. Kallan J.E., "Methodology and Assumptions for the Population Projections of the United States: 1999 to 2100", U.S. Census Bureau Population Projections Branch, Population Division, 2000.

5 Table 1, middle series and high series, report the Bureau's assumptions about net immigration levels under these projections. Table 3, middle series and high series, shows the percentage of the population will be of working-age (18 to 64) under different immigration scenarios.

6 See Table 2 on p. 15 of CBO report on S.744.

7 The paper, "Evaluating the Role of Immigration in U.S. Population Projections", which contains a detailed methodology, can be downloaded from the PAA website.

8 Table 1, middle series reports population projections form the Census Bureau.

9 See Table 2 on p. 15 of CBO report on S744.

10 Table 1 middle series shows the size of the Bureau's net immigration assumptions.

11 The key limitation to this approach is that CBO does not provide estimates of the ethnic composition of the new immigrants it expects will come under S.744. This is relevant because birth and death rates differ somewhat by country and region of origin. However, while this could impact births slightly, it would have a very small impact on the size of the foreign-born population, which is the primary focus of this analysis.