The initial September 11 release showed August US CPI rising 0.4% over the month and 3.4% over the year. Annual core inflation eased from July’s 2.5% to 2.4%, while monthly core inflation rose from 0.2% to 0.3%. A slower annual pace and faster recent increases appeared in the same report.
Gasoline rose 3.9% over the month, contributing more than a third of the headline monthly increase. Energy rose 2.1% and shelter 0.3%. Gasoline accounted for a substantial part of the total, but the faster monthly core reading left price pressure beyond energy. CPI and PCE have different baskets and weights; this core reading is not core PCE.
SPY and QQQ each gained about 0.9% that day, GLD 0.6% and TLT 0.1%. These closes do not identify CPI’s contribution or settle the following week’s policy decision. Equities, gold and long bonds had fallen together a day earlier; all closed higher in this session.
Historical backfill: compiled October 4, 2026, with observations limited to the date discussed and US prices through the September 11 New York close. Sources: BLS August CPI release, September 11, using its contemporaneous seasonally adjusted monthly and unadjusted annual figures; Yahoo Finance historical prices for SPY, QQQ, GLD and TLT, September 10–11. GLD is an ETF proxy. Inflation persistence and market interpretations are research judgments, not policy forecasts. This article presents personal research and opinion for informational purposes only and does not constitute investment advice.