The difference is in the detail


Investors who are looking to invest in commodities should be aware that while all of the three main commodity indices claim to offer a neutral and diversified exposure, they vary significantly in their constituent weightings.

Dow Jones AIG's Commodity Index, Diapason CM's Diapason Commodities Index (DCI) and S&P's GSCI all produce commodity indices, but provide different exposures.

John Prestbo, editor and executive director of Dow Jones Indices, says, "Our weightings are based on a combination of