U.S. stocks posted solid gains for the month and quarter with the S&P 500 delivering its best September performance in 15 years and capped its fifth straight winning month. Gains were driven by continued appetites for tech stocks while bond prices rose, and yields declined in anticipation of the Fed’s first interest rate cut of the year. Expectations for up to two more rate cuts this year have also boosted investor sentiment, along with solid corporate earnings and diminishing evidence that elevated tariffs have caused excessive inflation.