Wall Street ended the week in the red, driven by a sharp decline in UnitedHealth Group's stock following disappointing Q4 revenue results that fell short of analyst expectations. Despite the S&P 500 surpassing the 7,000-point mark for the first time in history earlier this week, the overall market was weighed down by significant job cuts at Amazon and a mixed performance from other major players. Technology stocks showed resilience, with Microsoft reporting strong Azure revenue growth of 39% year-over-year, while Tesla announced better-than-expected Q4 results.