Projected changes in the size of the U.S. population, as well as its age and sex composition, significantly affect the outlook for the economy and the federal budget. For example, the number of people who are employed and paying taxes on their wages depends on the size of the population ages 25 to 54, and the number of beneficiaries of some federal programs (including Social Security and Medicare) depends on the size of the population age 65 or older.*** In CBO’s projections, the population increases from 342 million people in 2024 to 383 million people in 2054, growing by 0.4 percent per year, on average, or by less than one-half the pace experienced from 1974 to 2023 (0.9 percent per year). Over the next decade, immigration accounts for about 70 percent of the overall increase in the size of the population, and the greater number of births than deaths accounts for the remaining 30 percent. After 2034, net immigration increasingly drives population growth, accounting for all population growth beginning in 2040. (For a comparison of CBO’s population projections with those of other agencies, see Appendix A.)
CBO’s projections of the population over the 2024–2054 period are highly uncertain, especially in later years. If rates of fertility, mortality, or net immigration were higher or lower than in the agency’s projections, then the resulting population would differ from the amounts shown here. The effects would be larger in later years of the projection period than in the earlier years because differences in those rates compound in each year of the period.
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| Source: CBO, Graphic by R L Rebach |
Full CBO document available in PDF format here.
