Fossil fuel use per capita shows a notable negative link with young adult female population
Comparing Fossil fuel consumption, per capita with Population ages 25-29, female, per capita across 202 countries, 2025–2025.
- Rank correlation
- -0.56
- Holding size constant
- -0.46
- Countries compared
- 202
- Period
- 2025–2025
What might link these
This suggests that countries with higher fossil fuel consumption per capita tend to have a smaller proportion of their population in the 25-29 female age group, even after accounting for population size and economic development. Potential explanations could involve differing demographic trajectories or societal structures influencing both energy use and birth rates, though this is highly speculative.
Why this is not proof of anything
This is a correlation across countries, not an experiment. It cannot show that either indicator causes the other, and both may simply follow a third thing. The strong negative correlation does not imply causation; societal development and historical factors are likely confounding variables.
The second figure above repeats the measurement with national population and income held constant. It is the more conservative number: a relationship that largely disappears there was mostly telling you that larger, richer countries have more of most things.
How this was measured
Both indicators were ranked across every country reporting each, and the two rankings compared — ranks rather than raw values, because a handful of very large countries can otherwise manufacture a relationship on their own. The calculation is arithmetic over figures already published on this site; the commentary above is drafted from the two indicator names and the resulting coefficients.