The “Magnificent Seven” group of high-performing tech stocks — Alphabet, Amazon, Apple, Meta, Microsoft, Nvidia and Tesla — has accounted for more than half of the gains so far this year as they benefit from intense investor focus on ways to play the artificial intelligence boom, according to S&P Dow Jones Indices.

Stocks fell in morning trading Friday as Wall Street closes out a holiday-shortened week. The S&P 500 fell 1.4%, with more than 80% of stocks in the benchmark index losing ground. Still, the index is managing to hold onto a modest gain for the week.