Excerpted from a Journal of Commerce Analysis:

East Coast ports maintained their lead in containerized exports in the first nine months of 2012 and increased their share of import and export markets. And they did so despite shipper concerns at the end of September over a potential strike by the International Longshoremen’s Association and a related shift of some cargo to ports on the West Coast and Canada.

Total U.S. exports through September 2012 were up 1.3 percent year-over-year and 1.6 percent from the same period in pre-recession 2008. East Coast exports advanced 2.1 percent year-over-year and 0.5 percent from the same period in 2008. Gulf Coast exports were up 5.1 percent year-over-year and 14.3 percent ahead of the first three quarters of 2008. The West Coast lagged, with volume slipping 0.4 percent year-over-year and flat with 2008, but it held a 40.9 percent share of the export market.

More at the JOC (subscription requited)