Equity index futures faced heavy selling pressure on Wednesday, with E-mini Nasdaq-100 futures leading the decline. The tech-heavy contract posted its largest percentage drop since July 23, falling about 4.5% from its all-time high amid a broader market pullback. Hotter-than-expected September inflation data served as the primary catalyst. Headline CPI rose 3.7% year-over-year, while core inflation climbed 2.6% annually—the fastest monthly pace since April. The strong data pushed the probability of an October Fed rate hike from 22% to 32%, driving Treasury yields higher and weighing heavily on growth-sensitive tech valuations. Semiconductor weakness amplified the selling after a major chip equipment manufacturer missed quarterly revenue estimates despite raising its 2026 outlook.