If you only watched the S&P 500 Index in July, you would think nothing happened. The index finished down just 0.1 per cent, still close to its record high. Beneath the surface, however, momentum had become almost synonymous with artificial intelligence and suffered one of its most violent crashes on record.Goldman Sachs estimates its high-beta basket fell 41 per cent, its technology basket plunged 48 per cent and its AI basket lost 38 per cent. Even after a record rebound, high-beta momentum ended July down 28 per cent, its worst month on record, while an index excluding the major AI enablers reached a fresh high.Subscribe to gift this articleGift 5 articles to anyone you choose each month when you subscribe.Subscribe nowAlready a subscriber? Fetching latest articles