The Baltic Exchange’s main sea freight index, which tracks rates for ships carrying dry bulk commodities, inched up on Monday, helped by firmer panamax rates. The overall index rose one point, or 0.21 percent, to 478 points. The index, which gauges the cost of shipping cargoes including iron ore, cement, grain and coal, and is seen by investors as an indicator of global industrial activity, touched an all-time low of 471 points on Dec. 16. Chinese imports of coal and iron ore have remained weak in recent months and worries over the health of the global economy have also dented dry bulk shipping prospects. The panamax index rose 7 points, or 1.64 percent, to 433 points. Average daily earnings for panamaxes, which usually carry coal or grain cargoes of about 60,000 to 70,000 tonnes, rose $52 to $3,462. The capesize index, fell 12 points to 512 points, while average daily earnings fell $34 to $5,156 points. Capesizes typically transport 150,000 tonne cargoes such as iron ore and coal.