According to strategists at Citigroup, excessively bullish positioning in U.S. technology stocks is exposing investors to the risk of a market reversal. The Citi team, including David Chaver, stated that sustained enthusiasm for the artificial intelligence theme has pushed bullish market bets to their limits, making the Nasdaq 100 index particularly vulnerable to shocks. "Concentrated long investments in this index 'increase the likelihood of profit-taking and long-term position unwinding triggered by any negative factors,' and the downside risk in the market is rising." Since bottoming out in late March, the S&P 500 index has risen by 20%, while the Nasdaq 100 has surged by 33%. According to momentum indicators, the Nasdaq 100 has remained in overbought territory for nearly the past six weeks. (Jinshi)