Mortgage bond prices slipped lower and the 10-year Treasury yield moved modestly higher this past week while the major stock market indices put in a mixed performance. While the Dow Jones Industrial Average and the S&P 500 saw some decent gains, the technology-heavy NASDAQ Composite Index took it on the chin following social media giant Facebook's 19% plunge on Thursday. Facebook's dive marked the largest-ever one-day drop in market value for a U.S.-listed company to the tune of -$119.1 billion.