U.S. stock benchmarks on Thursday finished a turbulent session mostly flat and the S&P 500 and the Nasdaq Composite eked out small gains to halt a multiday skid. However, the Dow Jones Industrial Averaged booked its third straight drop, representing its longest bout of losses since the five-session period ended June 18. The S&P 500 index /zigman2/quotes/210599714/realtime SPX -0.84% closed up 0.1% at 4,406, finishing higher for the first time in three sessions, while the Nasdaq Composite /zigman2/quotes/210598365/realtime COMP -1.92% closed up 0.1% at around 14,542, booking its first gain in four sessions. The Dow /zigman2/quotes/210598065/realtime DJIA -0.17% , however, declined 0.2% to 34,894, weighed by declines in Boeing Co. /zigman2/quotes/208579720/composite BA -1.92% , Caterpillar Inc. /zigman2/quotes/203434128/composite CAT +0.51% and Goldman Sachs Group Inc. /zigman2/quotes/209237603/composite GS -1.24% . Investors have grown cautious on stocks as concerns about the delta variant of COVID-19 threaten to dent the global economic recovery. Investors also are worried about the Federal Reserve's plans to taper its monthly purchases of bonds. But it was small-cap stocks that saw outsize losses on Thursday. The Russell 2000 Index /zigman2/quotes/210598147/delayed RUT -2.13% of small-cap stocks finished down 1.3%. The performance for markets came even as weekly data showed that jobless claims fell to a pandemic low of 348,000 last week.