The Baltic Exchange’s main sea freight index, which tracks rates for ships carrying industrial commodities, sank to a new record low for the sixth straight session on Tuesday. The overall index, gauging the cost of shipping dry bulk cargoes including iron ore, cement, grain, coal and fertilisers, fell 3.13 percent to 402 points. The index has fallen by about 14 percent so far this year. A downturn in dry bulk shipping amid a surplus of vessels has worsened in recent months as demand for iron ore and coal has declined due to slower economic growth in China. The capesize index shed 48 points, or 15.29 percent, sinking to its all-time low of 266 points. Average daily earnings for capesizes, that typically transport 150,000-tonne cargoes such as iron ore and coal, fell $333 to $3,261. Iron ore futures in China and Singapore dropped on Tuesday, extending recent losses on fears of more Chinese steel producers shutting, which could deepen a glut in the raw material. The panamax index fell nine points to 411 points. Average daily earnings for panamax vessels, which usually carry coal or grain cargoes of about 60,000 to 70,000 tonnes, decreased by $76 to $3,285.