A recent graph has been compiled showing trade volume against distance:-
We will be leaving the EU in 2019 and reduce trade with the countries represented by dark-blue dots and increase trade with the countries marked by light-blue dots.
However, in 2020 the IMO Low Sulphur Cap Fuel directive comes into play, see here: http://www.imo.org/en/mediacentre/pressbriefings/pages/mepc-70-2020sulphur.aspx which will dramatically increase the cost of transporting goods by sea over long distances. An assessment of the global economic impact is made over here: https://www.woodmac.com/analysis/IMO-2020-regulation-could-cost-shippers-billions – please think ahead, of where we will be in 2020?