The work stoppage, the first for the East Coast ports since 1977, is expected to impact more than 50% of U.S. imports.

JPMorgan estimates the economic loss from the shutdown of every major container port from Houston to Miami and New York-New Jersey will be between $3.8 billion and $4.5 billion per day.

Transportation and warehousing sectors are poised to first feel the pinch, with a broader economic fallout expected if the strike drags on.