What we got wrong, and when.

Corrections are published here and on the piece itself, with the original figure left visible. A figure is never quietly changed. The standard this holds us to is on the methodology page.

1. 2026-08-22 — The Spending Is Visible in GDP. The Productivity Is Not: This post originally led with the claim that AI investment had produced no measurable contribution to US GDP growth through 2025, and carried “Zero” as its headline figure. That was wrong. The Federal Reserve Bank of St. Louis measured AI-related investment contributing 0.97 percentage points to real GDP growth over the first three quarters of 2025, about 39% of all growth in the period. The headline figure is now 39%, and the piece has been rewritten around the distinction it originally blurred: the capital spending is plainly visible in the national accounts, while the aggregate productivity return is not. The sole source for the original claim was a personal blog post that has since gone offline; it has been replaced with the St. Louis Fed analysis, a Federal Reserve FEDS Note and a Kansas City Fed bulletin.