Studios benefit from these deals as they no longer have to pay to produce cassettes and discs themselves, and nor will they have to work out what to do with warehouses full of unwanted tapes when demand falls.

BBC: Movies on the web

Not only that, but this takes place after summer driving season, when demand typically falls off.

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At that time, three years of good weather produced bumper crops, and deep price falls when demand fell in world markets at the same time.

ECONOMIST: True grit

When the world slows down, demand falls.

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When the price of a television set or software package goes up, demand for it generally falls.

ECONOMIST: Buttonwood