General Motors’ October U.S. sales plunged 45 percent, and Ford’s and Chrysler’s weren’t far behind, as low consumer confidence and tight credit combined to bring the industry’s sales to an “unsustainably weak level” that is the worst in 25 years.

General Motors’ October U.S. sales plunged 45 percent, and Ford’s and Chrysler’s weren’t far behind, as low consumer confidence and tight credit combined to bring the industry’s sales to an “unsustainably weak level” that is the worst in 25 years.