One of Stanford’s original AI gurus says productivity liftoff has begun after doubling in 2025 amid transition to ‘harvest phase’ along J-curve

The K-shaped economy has dominated discourse lately, but the J-curve is entering the chat too amid debate over AI’s impact on productivity.

The curve refers to the idea that general-purpose technologies like AI don’t produce immediate benefits. Instead, massive investment comes first, obscuring early gains. It’s only after this initial dip that productivity really takes off, resulting in the J shape. But for some, it’s not clear yet that the transformation is happening.

Apollo Chief Economist Torsten Slok quipped that “AI is everywhere except in the incoming macroeconomic data,” recalling Robert Solow’s famous quote about the PC revolution. Slok added that employment, productivity and inflation stats are still not showing signs of the new technology. Meanwhile, profit margins and earnings forecasts for S&P 500 companies outside of the “Magnificent 7” also lack evidence of AI at work.

“Maybe there is a J‑curve effect for AI, where it takes time for AI to show up in the macro data. Maybe not,” he wrote in a Read Entire Article