Across the window SPY rose 1.3% to 767.18 on September 24 2026 (from 757.39 on September 15, peaking at 773.50 on September 21), QQQ rose 5.2% to 741.10, and IWM fell 1.2% to 281.66 after giving up 1.9% in the two sessions of the yield spike. The leadership is narrow - mega-cap AI up, small caps down - and the small-cap underperformance is the rate-sensitive channel the melt-up side cannot escape.