I was curious so I estimated. If we take daily intake at 8000 BTUs (~2000 calories), then we get 0.015Q BTUs in 1800 (US population: 5M[0]), 0.22Q BTUs in 1900

I was curious so I estimated. If we take daily intake at 8000 BTUs (~2000 calories), then we get 0.015Q BTUs in 1800 (US population: 5M[0]), 0.22Q BTUs in 1900 (US population: 76M), and 0.82Q BTUs in 2000 (US population: 223M). That's only humans. Factoring in all working animals, maybe we assume some multiple of that. 2x? 10x? 100x seems too much. In the end, I'm not convinced it would be significant enough to warrant inclusion - even if only because US population was so relatively small. This does lead me to wonder what the graph looks like for energy consumption per capita. [0] https://en.wikipedia.org/wiki/Demographic_history_of_the_United_States https://en.wikipedia.org/wiki/Demographic_history_of_the_Uni...