U.S. stocks ended Thursday with the worst declines in more than five weeks, with the S&P 500 closing below a key technical level. Technology and industrial sector stocks led the losses on the benchmark while all 30 components of the Dow industrials finished the day lower. The S&P 500 ended the day 21.85 points, or 1.2%, lower at 1,846.35. The Dow Jones Industrial Average dropped 231.19 points, or 1.4%, to 16,108.891, falling for the fourth consecutive day. The Nasdaq Composite shed 62.91 points, or 1.5%, at 4,260.42.