The container ship charter market, struggling to recover from record lows, is set to weaken further in 2013 with an overhang of excess capacity depressing vessel earnings, according to industry analyst Alphaliner.
Average charter rates this year have risen 20 percent from their all-time low in 2009, but remain 55 percent below their long-term 20-year average (unadjusted for inflation), making  2012 the second-worst year   for shipowners in the past two decades.
The rising volume of unemployed and laid-up ships is stifling efforts to raise charter rates, Alphaliner said.
The fleet of jobless vessels with capacity of more than 500 20-foot-equivalent units stood at 231 units with a total capacity of 820,000 TEUs at the beginning of December, including 53 that have been idle for more than six months.
Daily charter rates are between $5,000 and $9,000 for all ship sizes below 5,000 TEUs, with vessels of 1,000-2,000 TEUs faring comparatively better than 2,000- to 5,000-TEU ships, for which rates barely cover operating costs.
The high share of large and medium-sized ships in the 1.7 million TEUs of capacity scheduled to be delivered in 2013 will continue to exert downward pressure on rates for 2,000- to 5,000-TEU vessels, whose jobless rate has risen to 8.2 percent from 6.4 percent in August.
The 1,000- to 2,000-TEU segment should perform better, with an order book-to-fleet ratio of only 6 percent and an unemployment rate that has fallen steadily since August.