US Fertility Rate & Demographic Momentum Simulator

Simulated Year

2024

Sub-Replacement

Total Fertility Rate

1.60

-23.8% vs 2.10 threshold

Old-Age Dependency

29.4%

Seniors (65+) per 100 working

Projected Population

341.8M

+0.38% annual rate

Timeline & Scenarios 1960 — 2075

Timeline Scrubbing 2024

Target Future TFR (2030+) 1.60

Annual Net Migration 1.00M / yr

2024 Reality: US fertility sits at 1.60 births per woman, well beneath the 2.10 replacement threshold. Without immigration, cohorts begin contracting after generational delay.

Population Pyramid (5-Year Cohorts) Year 2024

Males (M)

Females (F)

Working Age (15-64)

Seniors (65+)

Generational Momentum: When TFR drops below 2.1, the pyramid base narrows immediately. Due to cohort momentum, overall population decline takes 20-30 years to manifest, while median age accelerates upward.