Indexes that track the prices of a specified group of commodities have become the subject of considerable controversy ever since 2008, when commodity prices bubbled and then crashed. The price crash was seen as a part of the larger U.S. economic collapse into a deep recession. Commodity index funds used investor money to go long futures contracts in the exact proportion as they were weighted in a particular commodity index. They had become an important part of the long side of a wide variety of commodity futures markets. In some markets index funds accounted for 30-40 percent of total open interest.Thanks to CFTC reports, the size of index fund long positions was highly visible. Index funds were and still are generally passive. They estab...