U.S. containerized exports jumped 12.5 percent, year-over-year, in April 2011, to a total of 1,076,113 20-foot equivalent units (TEUs), the 19th consecutive monthly year-over-year expansion for U.S. exports, said Mario Moreno, economist for The Journal of Commerce and PIERS.

The growth comes after a 13.9 percent year-over-year growth in March and left U.S. containerized exports up 12.3 percent through the first four months of the year.

"Despite a cooling in the manufacturing sectors of China and other key U.S. markets, U.S. containerized exports continued growing by a double-digit pace, partly aided by a weak U.S. dollar whose foreign value against a basket of major currencies fell again in April, this time by 1.8 percent over the average of March," said Moreno.

Gains were mostly driven by demand for paper and paperboard, up 12 percent or 15,766 TEUs; fabrics, including raw cotton, up 33 percent or 10,005 TEUs; and logs and lumber, which grew by 34 percent or 9,064 TEUs. Outbound shipments of motor vehicles displayed remarkable gains as well, jumping by 40 percent to a total of 40,526 TEUs. On the downside, pet and animal feeds fell by 19 percent or 10,420 TEUs, to a total of 43,711 TEUs.

Paper and lumber exports to China rose 12 percent or 24,068 TEUs to a total of 219,243 TEUs. Demand for paper and paperboard was up 22 percent, logs and lumber rose 90 percent. Increased bottle water demand in the aftermath of Japan's natural disasters fueled a spike in non-alcoholic beverage exports of 204 percent to a total of 5,684 TEUs.

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