Which U.S. president presided over the largest GDP growth adjusted for population?

1. FDR tops raw and per‑person growth — the wartime effect

Franklin D. Roosevelt ranks highest in historical tallies: Investopedia lists FDR with the highest average annual GDP growth at 10.1% and Statista shows the biggest rise in real GDP per capita during his term (about 5.25% annually) — both figures reflect economic mobilization for World War II and massive federal spending, not a steady peacetime expansion ^{[1] [2]}.

2. Why population adjustment matters — GDP vs. GDP per capita

Total GDP can rise simply because the population grows; the question you asked — “adjusted for population” — focuses attention on real GDP per capita. MeasuringWorth explicitly publishes annualized growth rates of real GDP and real GDP per capita across presidents and emphasizes per‑capita measures for fairer comparisons across different demographic eras ^[3]. Statista’s per‑capita chart also singles out FDR when the sample runs through 2011 ^[2].

3. Methodology and time‑period choices change the answer

Different datasets and endpoints produce different rankings. Investopedia’s headline number (10.1%) treats FDR’s term including wartime mobilization ^[1]. MeasuringWorth offers tables of annualized growth rates since 1900 and warns that choices — whether to include full terms, truncate at crises (e.g., COVID), or use 1900–2025 samples — matter when you rank presidents by growth ^[3]. Available sources do not spell out a single, universally accepted methodology for “largest GDP growth adjusted for population,” so conclusions must track the chosen metric and timeframe ^[3].

4. Modern presidents and partisan summaries — different lenses, different stories

For post‑WWII comparisons, some analysts and databases (Hudson Institute, AEA charts, Blinder & Watson cited on Wikipedia) show that Democratic presidencies have, on average, recorded higher GDP or GDP‑per‑capita growth since 1945 — but these are averages across many administrations and sensitive to start/end dates and recessions ^{[4] [5] [6]}. For cumulative percent real GDP over two terms, modern leaders like Bill Clinton register high rankings in some datasets ^[7].

5. Context: war, recovery, and recessions skew comparisons

High average growth rates during FDR’s presidency are historically unique because wartime production and emergency fiscal expansion propelled output; similarly, severe contractions like the 2020 COVID collapse distort short‑term presidential averages if included without adjustment ^{[1] [3]}. MeasuringWorth explicitly notes adjustments such as excluding anomalous pandemic years when comparing presidents ^[3].

6. What the empirical sources say you can confidently claim

• Franklin D. Roosevelt is listed as leading both total GDP growth and GDP per capita growth in multiple sources (Investopedia; Statista) ^{[1] [2]}.
• Scholarly compilations such as MeasuringWorth provide per‑capita annualized growth rankings and caution that results depend on sample choices and whether one uses real GDP or per‑person measures ^[3].

All other assertions about counterfactual causation or a single “best” president for growth are not settled in the cited reporting; available sources do not mention a single consensus beyond these rankings ^{[1] [3] [2]}.

7. Takeaway for readers and researchers

If your goal is a simple, population‑adjusted winner across the full historical record, FDR is the answer in the cited datasets ^{[1] [2]}. If you want a politically comparable, post‑1945 or peacetime comparison, use per‑capita series (MeasuringWorth, FRED) and be explicit about excluding wartime or pandemic distortions — sources show that rankings change when you change the metric or period ^{[3] [8]}. For any definitive policy claim about presidential “credit” for growth, the sources show you must pair the number with context about wartime mobilization, inherited trends and methodological choices ^{[1] [3] [2]}.