Average charter rates for containerships declined by 2.5 per cent in week 41 after decreasing by 3.3 per cent in the previous seven days, according to the Hamburg ConTex.

The volume of idle containership capacity, including charter-free tramp tonnage and idle and laid-up liner-controlled vessels, has risen by 90,000 TEU to 673,000 TEU - the highest level since March 2014, according to Alphaliner's end of September survey, reported IHS media.

Owners of very large charter vessels continue to face the strongest headwinds. The latest round of period fixtures show that charterers have managed to push rates for older post-Panamax vessels far below the US$10,000 a day barrier.

A case in point is the 5,900-TEU Folegandros which Maersk Line is reported to have chartered for three to 12 months to serve the trade between the Mediterranean and India at only $8,300 per day.

Alphaliner estimates the volume of idle tonnage in the 5,500-7,000 TEU segments at 34 units in spot positions globally, leaving little prospect for a rate rebound in coming months.

The ConTex 12-month period rate assessment for 4,250-TEU type vessels dropped by 6.5 per cent last week. Rates have settled in the low $9,000 per day range for very short periods, with COSCO reportedly fixing the 4,256-TEU Hammonia Granada at $9,250 per day.

Panamax charter vessels did well at the beginning of the year as congestion in US west coast ports prompted operators to hire dozens of "extra sailers" for services to the US west and east coasts.

However, with the opening of the new Panama Canal locks in the second quarter of 2016 and possible tonnage upgrades to post-Panamax a number of services, the segment may face turmoil next year.

"Panama services (in 2016) are expected to be rationalised into about 10 revamped loops, most of which will use ships of 6,000-10,000 TEU, while at least four of the nine services currently routed via Suez are expected to switch back to the shorter Panama route," said Alphaliner.