Why Stanley Black & Decker, ManpowerGroup, and Sage Therapeutics Slumped Today

Friday was a poor day on Wall Street, as the Dow Jones Industrialsfell 200 points and other major benchmarks lost about 1%. Rising bond yields were a major source of consternation among those following the financial markets, with the 10-year Treasury hitting 2.95% and helping to send mortgage rates sharply higher.

Even though earnings season has gone fairly well for many companies, some investors are also starting to realize that political issues are likely to cloud the outlook for the U.S. economy in the coming months, creating more uncertainty that could stymie further market gains. Some bad news affecting individual companies also added to the negative mood. Stanley Black & Decker (NYSE: SWK), ManpowerGroup (NYSE: MAN), and Sage Therapeutics (NASDAQ: SAGE)were among the worst performers on the day. Here's why they did so poorly.