Jonathan Hogg and Karan Jalan

A flag flies outside the Baltic Exchange in London, U.K., on Wednesday, June 16, 2010. The Baltic Dry Index, a measure of commodity-shipping costs that's tumbled 28 percent during its longest losing streak this year, may decline further, according to technical analysis by Barclays Capital. Photographer: Chris Ratcliffe/Bloomberg

Macro funds can make waves with exposure to global shipping

Commodities are a staple of any diversified investment portfolio, but few investors factor in the cost of sea routes. Can freight rates...