A range of companies headquartered in the greater Valley region suffered falling stock prices Tuesday, pulled down by a market that saw the Dow Jones Industrial Index lose nearly 800 points. Among the Valley’s largest companies, Penny Mac Financial Services Inc. in Westlake Village lost 7.7 percent, Asgn Inc. in Calabasas fell 7.3 percent, Sylmar construction firm Tutor Perini Corp. declined 6 percent, Teledyne Technologies Inc. in Thousand Oaks lost 5.5 percent and California Resources Corp. dropped 5.4 The region’s two largest public companies, Walt Disney Co. in Burbank and Amgen Inc. in Thousand Oaks, fell 2.5 percent and fell 2.6 percent, respectively. In the broader market on Wall Street, the Dow Jones Industrial Index fell 799 points, or 3.1 percent, and the Nasdaq lost 283 points, or 3.8 percent.