Commodity index advocates stick to their guns

Ten years after publishing an influential paper that fuelled the commodity investment boom, Yale professors Gary Gorton and K Geert Rouwenhorst have revisited their study and found their arguments still "largely hold up". But critics are quick to disagree

Surprise: a new paper promotes the benefits of commodities investment, amid tumbling prices for commodities such as crude oil, copper and gold

The year 2015 has proved to be something of an annus horribilis for investors in long-only commodity index products. As prices for commodities such as crude oil, copper and gold have tumbled in recent months, broad indexes such as the S&P GSCI and the Bloomberg Commodity Index have hit their lowest levels in more than a decade.

So it may come as a surprise that two of the original evangelists of the commodity index boom of the 2000s – Gary Gorton and K Geert Rouwenhorst, now both finance