Core vs Headline Inflation: Why the Two Numbers Diverge (September 2026)
The two numbers on your screen, answered first In September 2026, U.S. consumer prices rose 3.7% from a year earlier. Core prices, which leave out food and energy, rose 2.6% . Believe both numbers — but use them for different jobs. The 3.7% is what American households actually paid. The 2.6% is the best read of where inflation is headed. Almost the entire gap between them is one thing: gasoline, up 34.2% from a year earlier. All figures in this post come from the Bureau of Labor Statistics (BLS) Consumer Price Index release for September 2026 (USDL-26-1574, published October 14, 2026), unless noted otherwise. What each number actually measures Headline inflation is the change in the full Consumer Price Index for All Urban Consumers (CPI-U): the whole basket — groceries, gasoline, rent, haircuts, car insurance, all of it, weighted by how much households actually spend on each category. Core inflation is the same basket with two categories removed: food and energy. Its official n...