US stock index futures fell on Wednesday, with concerns in the market about whether NVIDIA can once again present a surprising financial report. Investors are also beginning to question whether the artificial intelligence boom can continue. Goldman Sachs trading department refers to NVIDIA as "the most important stock on Earth" due to its high weighting, which could potentially shake up the market. NVIDIA is at the core of the AI revolution, and after more than doubling its stock price in 2023, it has also shown leading performance in the SP 500 index this year. Justin Onuekwusi, Chief Investment Officer at St. James's Place, said: "It feels like today's post-market performance of NVIDIA in US stocks will be a barometer for global cycles; when the stock market focuses on one company's performance, macro effects may occur. This is not just an issue of building investment portfolios but an unavoidable macro challenge."