Sentence:  It argued , inter alia , that a divestiture order would severely depress the market value of the stock of both General Motors and du Pont , with consequent serious loss and hardship to hundreds of thousands of innocent investors , among them thousands of small trusts and charitable institutions ; that there would be a similar <WSD>decline</WSD> in the market values of other automotive and chemical stocks , with similar losses to the stockholders of those companies ; that the tremendous volume of General Motors stock hanging over the market for ten years would hamper the efforts of General Motors and other automobile manufacturers to raise equity capital ; and that all this would have a serious adverse effect on the entire stock market and on general business activity . 
Meaning of the word marked with <WSD> tags:  a gradual decrease; as of stored charge or current