One line of evidence that AI could spark explosive growth is the Industrial Revolution precedent. UK per‑capita GDP grew at 0.07% annually from 1252‑1652, then rose to 1.02% by 1850, a 15‑fold acceleration. Some argue we should expect similar 10× jumps today.

The post tests two claims: early Industrial growth often exceeded 10× the long‑run average, while today such 10× years are rare. Using year‑to‑year variation, an IR‑style acceleration would push frontier economies to about 2.8% annually, far below the 10× claim.

Skepticism about 20% annual growth is understandable; in the 1700s a 10× jump would have seemed plausible because the necessary rate already occurred frequently. Today the dynamics are qualitatively different, falling several standard deviations outside current norms, making such growth unprecedented for contemporary observers.

Evidence shows 10× faster growth was common pre‑Industrial: about 46% of years (1252‑1652) and 17% of 20‑year windows exceeded a 0.6% threshold. Modern analogues (8 countries) saw 19% of years surpass a 3.5% threshold, and 94% of slow‑growing economies recorded at least one 10× year. All estimates rely on the Maddison Project Database 2023, which provides GDP per capita in 2011 USD and population figures.