According to Ethan Mollick on Twitter, a project run with ChatGPT-5.4 Pro estimates that only about 1.5% of the roughly 117 billion humans who have ever lived achieved a lifestyle comparable to today’s middle-class in middle-income countries, highlighting the unprecedented living standards of the present (as reported by Ethan Mollick on Twitter). According to Mollick, the AI-assisted methodology underscores how modern prosperity is historically rare, suggesting opportunities for AI-driven policy simulation, economic history modeling, and counterfactual analysis to quantify welfare gains across eras (according to Ethan Mollick on Twitter). For AI businesses, this points to demand for GPT-class tools that combine historical datasets, economic indicators, and demographic time series to produce reproducible welfare estimates, benchmarking frameworks, and decision-support dashboards for governments, NGOs, and impact investors (as reported by Ethan Mollick on Twitter).