The trade volume at the Shanghai Port, which comprises one quarter of China's total foreign trade, continued to decline in December, according to local Customs data.
Imports and exports at the port amounted to $43.48 billion in December, down 8.8 percent year-on-year.
Traffic at the port increased rapidly for the first seven months of 2008, but trade volume started to drop during the last two months.
In November, trade volume plunged by 9.7 percent year-on-year, down sharply from the 15.7 percent annual increase in October, making it the largest monthly decline since China joined the WTO in 2001.
Trade volume at the port surpassed $600 billion in 2008, up 16.3 percent year-on-year. The increase rate, however, dropped by 5.3 percent from the previous year. Exports were up in 2008 by 19.9 percent to $393.65 billion, and imports were up by 10.3 percent to $213 billion.