S&P, Nasdaq Fall; Dollar Rallies After Trump Taps Warsh

Market Overview - Major indices finished the month of January with gains despite volatility, with the Russell 2000 being the biggest gainer at up 3% [8] - The S&P 500 saw a slight increase of 1.3% overall for the month [3] - On the final trading day, the Dow Jones Industrial Average was down 0.4%, the S&P 500 down 0.4%, the Nasdaq down 0.9%, and the Russell 2000 down approximately 1.5% [7] Company News - Peloton announced a staff reduction of 11%, including from engineering teams, leading to a 2.5% drop in shares as part of a cost-cutting strategy [5] - Deckers, owner of UGG and HOKA brands, was the top gainer in the S&P 500, rising 19% after raising its annual earnings and sales forecast [11] - SanDisk experienced significant volatility, with shares up 25% at one point during the day but closing up just shy of 7% [12] - A company reported the largest gain in mobile phone subscribers since 2019 and plans to buy back up to $25 billion in shares, resulting in a nearly 12% gain in its stock [16][17] - Rocket Companies saw a decline of 13.7% following disappointing earnings from PennyMac Financial Services, which reported profits significantly below expectations [19] - Unity Software lost nearly 25% of its market cap in a single day due to a product announcement from Google, while Take-Two Interactive fell 8% [20][21] - Bombardier shares dropped 6.6% after President Trump threatened tariffs on Canadian aircraft, although analysts believe the threat may be exaggerated [23][24]