Stock Market Rally Risks Losing Steam as Economic Bounce Fades

US stocks have defied skeptics this year as they climbed to records despite a global trade war, lingering fiscal fears and September’s gloomy reputation. But for investors fretting about the rally’s durability, the economy may be sending a warning that the momentum is about to fade.

The S&P 500 Index has added $15 trillion in market value since early April and notched 27 records in 2025. Its 34% gain over the last five months — led by a surge in Big Tech shares — is a feat topped in just four other instances since 1950, according to data compiled by Bloomberg.