Almost half of S&P 500 margin expansion is coming from tech, the largest share in decades, perhaps ever. As various studies have shown, tech tends to be the primary beneficiary of tech—in productivty and in margins—and that narrowness persists and is widening.

Source:
1/ https://www.apolloacademy.com/sp-500-margin-expansion-all-coming-from-tech/
2/ https://www.chicagofed.org/publications/chicago-fed-letter/2025/515?utm_source=chatgpt.com