A small correction for CBO history buffs... We revised this piece to note that CBO applied the population-change approach to Senate Amendment 1150 to S. 1348 as well. Grateful to Donald Marron for discussions that highlighted this unintentional omission.

We are also grateful to several staff of the Congressional Budget Office and the Joint Committee on Taxation, as well as Doug Holtz-Eakin and Donald Marron, for technical feedback on this work.

Doug and I are very grateful to Alex Arnon and Kent Smetters for making possible this collaboration with the Penn Wharton Budget Model team.

The budget estimates presented in this policy brief show that conventional and population-change approaches can result in sharply divergent estimates of the federal budgetary impact of at least some immigration-related legislative proposals.

Our goal in undertaking this work is to provide additional information to CBO and JCT, to Congress and the relevant Congressional committees, and to the public about the implications of the choice of estimation approach for legislative proposals addressing immigration.

Over the following decade, the difference is even larger – changing from a $74 billion increase in the federal budget deficit under the conventional approach to a $634 billion decrease under the population-change approach.

The difference between these two approaches is stark, changing from an increase in the federal budget deficit by $4 billion under the conventional approach, to a net decrease in the federal budget deficit of $129 billion under the population-change approach, from 2025 to 2034.

Following the population-change approach, PWBM analysts estimate that a proposal similar to Section 80303 in H.R. 4521 would, on net, decrease the federal budget deficit by $129 billion from 2025 to 2034.

Under such a population-change approach, immigration proposals similar to Section 80303 in H.R. 4521 have been estimated by CBO and PWBM to decrease federal budget deficits, reflecting increased collections of individual income taxes and payroll taxes. www.cbo.gov/publication/...