Leading shipping lines boosted their capacity by 14% in 2010, with MSC closing the gap on the world’s largest carrier, Maersk Line.

The total capacity operated by the top 20 carriers had reached 12.3 million teu by the start of this year, compared with 10.8 million teu a year ago and 10.6 million teu in January 2009.

Of the industry’s leading shipping lines, MSC recorded the largest increase in its fleet, in terms of capacity added, closing the gap on Maersk Line by bringing in an extra 375,000teu – a 25% increase. Meanwhile, Maersk’s fleet grew by around 5%.

Maersk now operates 14.5% of the containership fleet, compared with 15% at the beginning of last year, while MSC has lifted its market share to 12.6% from 10.9% a year ago.

But Maersk Line told IFW’s sister publication, Lloyd’s List, it had no intention of letting its position as market leader slip.

Head of network and products Lars Reno Jakobsen said Maersk’s long-term objective was “to grow with or more than the market and maintain our market leader position”.

Industry speculation suggests the Danish carrier is planning to order a series of 18,000teu vessels. They would be the largest containerships ever built.

In terms of percentage growth, Chilean shipping line CSAV led the field, increasing its fleet by 74% from 333,000teu to 579,000teu.

The market share of the top 20 carriers as a percentage of the global liner fleet increased from 79% to 83%.

Overall, the total cellular fleet stands at 4,849 ships representing 14.2 million teu, up 9.1% in nominal capacity terms compared with 12 months ago.

The recovery seen in volumes over the last 12 months is reflected in the reduction in the size of the top 20 carriers’ idle fleet, which this time last year stood at 740,000teu, or 6.9% of the total fleet, but is now 136,000teu, just 1.1% of the total fleet.

Analyst Alphaliner said 18 of the top 20 carriers had increased their operational capacity over the past 12 months, with only NYK and K Line logging a decline.