A potentially historic drop for Alphabet's stock is dragging the US market lower Thursday after the company behind Google and YouTube reported weaker growth for the summer than analysts expected. Alphabet is one of the most influential stocks on Wall Street because it's one of the largest, and its 12% drop is on track to be its worst since it began trading more than 20 years ago, the AP reports. It was under heavy pressure to at least meet analysts' expectations for growth amid concerns about how much it's spending to invest in AI.