Economists grossly underestimated June trade deficit drop

Fox business is reporting that the Commerce Department reported the U.S. trade deficit fell 10.7% to $42.9 billion in June from the month before. The deficit was the narrowest since December 2010 and considerably smaller than the $47.5 billion economists expected.

This seems to be a HUGE miscalculation. Is it normal to miss these things by this much? Or is there something screwy going on here?