Wealth Concentration & Tax Rates in America

100 years of data — Does lower taxation on the rich correlate with rising inequality?

Chart 1: Top Marginal Tax Rate vs Top 1% Income Share (1920–2024)

Key finding: When top marginal rates were 70–94% (1940s–1970s), the top 1% captured ~8–11% of income. As rates fell to 28–37% (1980s–present), their share rose back to ~20%. The correlation is striking and nearly inverse.

Chart 2: Who Owns America? Wealth Share by Group (1989–2025)

Key finding: The top 1% went from 23% to ~30% of all wealth. The bottom 50% — half of all Americans — went from 3.5% down to a low of 0.4% in 2011, and only recovered to ~5% by 2025. The top 10% combined owns ~64% of everything.

Chart 3: Effective Tax Rate (All Taxes) — Rich vs. Everyone Else

Key finding: In the 1950s, the top 1% paid an effective rate of ~42% across all taxes. By 2018, this fell to ~26%. Meanwhile, the middle class rate barely moved (~17–20%). The system went from strongly progressive to nearly flat. By Saez & Zucman's calculation, in 2018 the richest 400 families paid a lower effective rate (23%) than the bottom 50% (24.2%).

Chart 4: Top Marginal Income Tax Rate (1913–2024)

Key finding: The top rate was 91–94% for two decades (1944–1963). America built the interstate highway system, went to the moon, and created the largest middle class in history during this period. The rate has been 37% since 2018.

Chart 5: Wealth Growth Since 1989 — Who Won and Who Lost?

Group1989 Wealth Share2024 Wealth ShareChangeReal Wealth Growth
Top 1%22.8%30.5%+7.7 pts+300%
Next 9% (90–99th)33.2%35.1%+1.9 pts+150%
Next 40% (50–90th)40.5%31.0%-9.5 pts+50%
Bottom 50%3.5%2.5%-1.0 pts~0%
Key finding: Since 1989, the top 1% gained ~$30 trillion in wealth (+300%). The bottom 50% — 65 million households — experienced effectively zero net wealth growth over 35 years. The middle class (50th–90th percentile) lost 9.5 percentage points of their share of the national pie. The winners: the top 1% and especially the top 0.1%.

Chart 6: The Great U-Turn — Top 1% Wealth Share (1913–2024)

Key finding: Wealth concentration follows a U-shape over the last century. It was extreme in the Gilded Age (~45% in 1913), fell dramatically through progressive taxation and New Deal policies to ~22% by the late 1970s, then climbed back to ~31% today. We are approaching — but haven't yet reached — Gilded Age levels.

Verdict: Does the Data Support Your Theory?

Mostly yes. The data strongly supports these conclusions:


1. Wealth concentration HAS gotten worse — but with a caveat.
It's a U-shape, not a straight line. Concentration was extreme in 1913–1929, fell dramatically mid-century, and has risen sharply since ~1980. Over the last 45 years, the trend is unambiguously toward greater concentration.


2. Tax rates on the rich DID fall dramatically.
Top marginal rates went from 91% → 37%. Effective rates on the top 1% fell from ~42% to ~26%. The tax system shifted from strongly progressive to nearly flat. By some measures, billionaires now pay lower effective rates than working-class Americans.


3. The correlation between lower taxes and rising inequality is strong.
The timing matches almost perfectly: inequality bottomed out when taxes were highest (1950s–1970s) and rose as taxes were cut (1980s–present). However, correlation ≠ causation — globalization, technology, financialization, union decline, and policy changes all contributed.


4. Who is richer now? The top 1%, and especially the top 0.1% and billionaire class. Their wealth grew 300%+ since 1989.
Who is poorer (relatively)? The bottom 50% saw ~0% wealth growth in 35 years. The middle class (50th–90th percentile) lost 9.5 points of wealth share. They aren't necessarily poorer in absolute terms, but they own a shrinking piece of a growing pie.


5. Did taxes "exponentiate" the gap? "Exponentiate" is actually the right word. Wealth compounds — it earns returns on itself. When effective tax rates on capital gains, estates, and top incomes are low, wealth compounds faster for those who already have it. The rich don't just earn more — their wealth multiplies faster when tax rates are low. This is the mechanism your theory describes, and the data supports it.

Sources

Stay alert to major economic moves

Get one email when a major U.S. economic indicator shifts — from housing to inflation to employment.