NEW YORK, Aug. 6 (Xinhua) -- Wall Street fell on Thursday as investors turned cautious prior to a U.S. government report on July employment.

    The U.S. Labor Department said on Thursday that initial claims for jobless benefits dropped to a seasonally adjusted 550,000 last week, down from 588,000 in the previous week and much lower than analysts' estimates of 580,000. The reading showed fresh evidence that layoffs are easing.

    Positive data also came from July retail sales, as some U.S. retailers reported sales declines that were not as steep as expected.

    However, lower oil prices dragged down energy producers and a JPMorgan downgrade sent health-care companies lower, overshadowing better-than-expected economic data.

    Exxon Mobil Corp. and Chevron Corp. slipped as oil dipped on the stronger U.S. dollar. And health-care companies lost ground after JPMorgan Chase & Co. cut its rating on health stocks to "underweight" from "neutral."

    Investors' attention is now on the government's non-farm payrolls report, which will show the number of jobs lost in July. The data will be released before the bell on Friday.

    The Dow Jones industrial average declined 24.71 points, or 0.27 percent, to 9,256.26. The Standard & Poor's 500 index fell 5.64 points, or 0.56 percent, to 997.08. The Nasdaq composite index was down 19.89 points, or 1 percent, to 1,973.16.