In economics we can often observe the fact that a dependent variable is not always able to move immediately after a fortuitous change in an independent variable.

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With this sort of contract, the owner of a big, highly appreciated stock position gets an upfront payment from an investment firm--typically for 75% to 85% of the value of his shares--in exchange for agreeing to deliver a variable number of shares or cash in the future, with the exact amount dependent on how the stock performs.

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