For the six-month period, the association noted that shipments of shellfish, principally clams, to the US shot up roughly 78.3% on the back of food safety concerns over imports from the Republic of Korea. The US combined with Japan and the EU account for an 85% market share and all three markets saw overall improved sales for the January-June period, said the association, while consignments to ASEAN nations collectively declined by nearly 22.7%.