
Shares of health insurer UnitedHealth Group UNH.N fall 6.2% to $355.15 premarket
CEO Andrew Witty decides to step down for personal reasons; co appoints Stephen Hemsley as new CEO effective immediately
Co also suspends 2025 outlook as medical expenditures expected to be higher than anticipated
UNH expects to return to growth in 2026, co says
Up to last close, UNH down 25.1% YTD