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Perpetual Contract(R) Charts
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| · | The original formula uses Time Weighting and represents a weighted average of the two contracts of the same commodity that lie adjacent to a given period-forward point in time, avoiding the volatile expiring market period and the quiet illiquid period of a contract's history. 
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| · | The alternative Perpetual Contract series uses Open Interest Weighting to blend all contracts, with emphasis on those with the greatest open interest.
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