Investor interest in commodities, including oil, has risen dramatically over the last decade and commodities have become a new asset class in institutional investors’ portfolio. Partly, this development is due to diversification benefits. In addition, the development of new investment vehicles, such as exchange traded funds, has allowed individual investors to get exposure to movements in commodity prices. Due to the storage and trading costs associated with direct physical investment in commodities, the main vehicle used by investors to gain exposure is via commodity indices (baskets of short maturity commodity futures contracts that are periodically rolled over as they approach expiry), exchange traded funds or other structured products. These instruments provide generally long-only exposure to commodities.