The success of a futures contract depends on liquidity. Volume is a critical component of success. Additionally, open interest, or the total number of open long and short positions, must be at a critical mass to make a futures contract useful for consumers, producers, and speculators. A lack of liquidity makes the differential between bids and offers wide, which inhibits hedging and speculative activity. Moreover, illiquid markets tend to hit price vacuums, where sellers find it impossible to execute sales in a falling market, or buyers cannot make purchases when the price is rising.
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