The index tracks the performance of domestic and foreign, including developing and emerging, small- and mid-capitalization companies that are involved in the gold and silver mining industry. The fund invests at least 80% of the fund"s net assets in swap agreements, futures contracts, or short positions, that, in combination, provide 2X daily inverse (opposite) or short exposure to the index or to ETFs that track the index, consistent with the fund"s investment objective. It is non-diversified.