GENEVA -- International shipping volumes gained 4% in 2011 to a record 8.7 billion tons even as prices fell sharply owing to surplus capacity, a United Nations think tank said Tuesday.

Despite increasing demand, "world ship supply capacity expanded much faster, at a rate of 10% cent, reaching for the first time a total of 1.5 billion deadweight tons," the UN's Conference on Trade and Development's (UNCTAD) Review of Maritime Transport 2011 explained.

The indicators are important because about 80% of global trade is transported by ship, UNCTAD noted.

As an indication of the falling prices, the cost of transporting a 20-foot container from Shanghai to northern Europe plunged from $1,789 in 2010 to $881 in 2011, the think tank said.

The average cost of shipping a 40-foot container from Shanghai to the U.S. West Coast fell over the same period from $2,308 to $1,667, according to the UN report released in Geneva.

And in a "remarkable shift" away from previous years, developing country ports took a far greater slice of the global shipping sector pie than before, UNCTAD said.

In developing countries, ports loaded 60% and unloaded 57% of world seaborne trade by volume, the report showed.

Meanwhile, in a sign of declining competition in the industry, the average number of shipping companies dropped by nearly 23% between 2004 and 2011, UNCTAD said.

During the same period, the size of the largest ship deployed nearly doubled, it noted.

Copyright Agence France-Presse, 2012