The slumping U.S. stock market wiped out more than $10 trillion in wealth in 2022, and half that total was accounted for by just seven companies, according to a year-end study by Howard Silverblatt, senior index analyst at S & P Dow Jones Indices. Most of the decline came in S & P 500 stocks, which lost a combined $8.2 trillion. Although tech stocks accounted for a majority (43% of the $8.2 trillion), it's worth noting that losses in consumer discretionary (23%) and communication services (21%) companies together chipped in an even larger amount. Losses were concentrated at the top of the food chain. Amazon, Apple, Alphabet, Microsoft, Tesla, Meta Platforms and Nvidia lost a combined $4.95 trillion in market capitalization in 2022. In other words, those seven companies accounted for some 60% of all the losses in the S & P 500. Of those seven megacaps, losses ranged from Amazon's plunging market value of $844 billion to Nvidia's decline of $388 billion. In all, 15 companies in the S & P 500 that each lost at least $100 billion accounted for a combined 70% of the entire index's declining market value in 2022. Broken down by the index's 11 major industry groups, information technology's market value slid $3.49 trillion, trailed by consumer discretionary stocks, dominated by Amazon, Tesla, Home Depot, Nike, Lowe's and Target, at $1.91 trillion. Communications services companies, led by Alphabet, Meta, Netflix and Disney, slumped a combined $1.76 trillion. The smallest decline was in consumer staples, at just $38 billion, while energy stocks were only one of two sectors to post any gain, rising $592 billion in value. Utilities added $22 billion in value in 2022. Silverblatt used the S & P U.S. Broad Market Index, consisting of roughly 2,500 stocks, to measure the total market decline of $10 trillion. —CNBC's Christina Cheddar Berk contributed to this report.