SHANGHAI (Bloomberg) ? China, the world?s third-largest shipbuilding country, needs to add 31 million tons of freight capacity over the next five years to meet increased demand for sea freight, the nation?s biggest shipbuilder said.

The nation needs to acquire 6.2 million so-called deadweight tons of container ships, oil tankers and bulk carriers each year for five years, Dong Qiang, vice president of Beijing-based China Shipping Industry Corp., said at the World Shipping Summit in Shanghai yesterday, without giving the current capacity. Deadweight tons include the weight of the ship, cargo and fuel.

About 20 million tons of the new capacity will meet increased freight demand while the remainder will replace ageing ships, Dong added.

China?s economy has expanded an average 8.7 percent a year in the past decade, fueling demand for metals for bridges, buildings and cars, and driving prices of iron ore and coal to records.