1. The Future of American Religion to 2050 Vegard Skirbekk Institute for Applied Systems Analysis (IIASA), Eric Kaufmann Birkbeck College (U. London) & Harvard KSG Belfer Center Anne Goujon IIASA

2. Context and Data US Census Bureau Race Projections to 2050 No census question But can use large surveys (GSS), plus census and immigration statistics Pew 2007, 2008 surveys for small groups

3. Methodology Cohort Component Projections Multi-State Projection (PDE) Software Inputs (for each group, by 5 yr age bands and sex): –Base Population –Total Fertility Rate (TFR) –Net conversion/apostasy per year –Net immigration per year –Mortality (standard)

4. Resident population Net immigrants Immigration based on numbers acquiring citizenship in 2003-6 (Homeland Security) 1.2m per year Faith of immigrants computed from source countries x religious composition of source countries (CIA Fact Book) Catholic and Other overrepresented, Protestants underrepresented

6. Fertility and Population Share, 2003-43

7. Proportion of Jews and Muslims in the American Population and Electorate (Constant Scenario) Source: GSS; Author’s calculations

8. White Voting Age Population

9. Fertility and Population Share, 2003-43

10. Fertility Differentials ConversionMigration ConstantDoublesHalfZero Constant H0H1H7H4 ZeroH3 H5 Converging ConstantH2 Zero H6

11. Ethnoreligious Categories by Religious Attitude (%) Anti-Abortion Anti- Homosexuality Jewish287 Hindu/Buddhist3313 No Religion3712 Other non-Christian5021 Muslim5533 Liberal Protestant5523 Moderate Protestant5927 ‘White’ Catholic6420 Black Protestant6630 Hispanic Catholic7224 Fundamentalist Protestant7433 Total5924 Source: GSS 2000-2006

12. Total Fertility Rate by Religious Attitudes, 2003 Fundamentalist vs. Liberal Protestant Fundamentalist vs. No Religion Homosexuality Always Wrong (Y/N) Abortion Always Wrong (Y/N) Traditionalist TFR2.13 2.502.47 Modernist TFR1.841.661.981.83 Difference in percent16285264 Source: GSS 2000-2006 Traditionalist-Modernist Fertility Gap, Children Ever Born (CEB), for Women 40-59 Source: GSS 1972-2006 Abortion Always Wrong (Y/N) Homosexuality Always Wrong (Y/N) pre-19851.221.11 1986-951.281.16 1996-20061.38 1.21

13. Projected Trends in Opinion Under Various Scenarios

14. Conclusions: Market Share Main drivers to 2043 are immigration and secularization, fertility matters more long term Conversion favours Fundamentalist Protestants but is not large enough to compensate for immigration of Hispanic Catholics and rise of No Religion Fundamentalist Protestants will decrease in total, among whites, and among voters Muslims will outnumber Jews by approximately 2020 Jews, white Catholics and liberal Protestants will decline Protestants decline from a majority in 2003 to 40 percent by 2043; Catholics may outnumber Protestants by mid-century

15. Conclusions: Religiosity Seculars will increase their share of the white population but not of the total population Secularization will plateau by 2043 and will reverse thereafter. Secular-Religious Fertility differences between partisans on opposite sides of 'culture war' issues are substantial and growing Opinion on abortion is likely to become more pro- life Attitudes regarding homosexuality will be stable, reflecting more liberal attitudes among younger cohorts but more conservative attitudes among demographically-growing groups

16. The Future of American Religion to 2050 Vegard Skirbekk Institute for Applied Systems Analysis (IIASA), Eric Kaufmann Birkbeck College (U. London) & Harvard KSG Belfer Center Anne Goujon IIASA

17. Current TrendZero Immigration

18. Projections fit observed changes

19. Size of five aggregated rel i gious groups