I've not made any estimates of the split of goods between North or South.
Wouldn't it make more sense to go directly to the southern ports and tranship the tiny percentage of goods destined for the North from there?
In other words, ship the Northern goods to the South, then turn around and ship them up the east coast part way back to Europe the way they came? It is a wonder you Yankees won the war.
Well, yes, since so much was destined for the south anyway and comparatively little was destined for the North. Or so the sothron economic giants like GOPConservative assure us. And one possible reason why the Yankees won the war was that they were familiar with the prevailing wind patterns of the Atlantic. Prevailing winds run clockwise around the North Atlantic so that the prevailing westerly winds are in the south and the prevailing easterly winds are in the north. So ships bound for the United States would tend to swing a bit south anyway rather than go on a direct line from England to New York. I guess that's why the southern planters stayed away from the shipping business, the fools would be trying to go west in the teeth of the eastern prevailing winds. Not very successful.