The Reuters article '米GDP確報値、第4四半期は0.5%増に下方改定 前期から大幅減速' directly states that the U.S. Commerce Department revised Q4 2025 annualized GDP growth down to 0.5% from 0.7%. Search corroboration also points to the official BEA release URL 'Gross Domestic Product, Fourth Quarter and Year 2025 (Third Estimate), Corporate Profits' and to consistent secondary summaries such as 'United States GDP Growth Rate' and 'US GDP expands at annual rate of 0.5% in Q4 vs 0.7% expected'. I could not validate the BEA page directly because the fetch failed, but the available evidence is consistent and strongly supports the claim.