Trading cycle
A trading cycle was the upward and downward trends of the trade value of an item as determined by a set period of time so as to determine the item's growth.

When the Ferengi petitioner, Daimon Igel, asked Grand Nagus Zek "whether he should sell his duranium interests on the open market or on the Futures Exchange." Zek, found it to be an interesting question and requested from Quark to see how duranium had been doing. 

In reviewing the data, Quark revealed that "Over the last three trading cycles there's been an increase of 7¾, a decrease of 2⅛, and another increase of 11⅜" – which indicated an overall gain of seventeen points. ()

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Economics