At present, the S&P 500 index has registered a 0.4% increase, while the Dow Jones index has experienced a slight 0.1% decline. Notably, General Motors' stock price has plummeted by over 1.9%. In a recent announcement, US President Trump stated that, commencing November 1, a hefty 25% tariff will be levied on all medium-sized and heavy-duty trucks entering the United States.