Nvidia alone accounts for more than a third of the S&P 500's gains this year—and it's a big risk for investors, top economist warns

Nvidia's stock has soared 166% from the beginning of the year to date, according to the information provided. The impressive increase has been driven by the artificial intelligence craze that has gripped Wall Street, with Nvidia being a leading player in the AI chip industry.

Nvidia's current market valuation is $3.014 trillion. This is a significant increase compared to its valuation a year ago, which was around $950 billion. The ongoing AI boom has played a major role in catapulting Nvidia's market valuation to the $3 trillion club.