Because the net cost of membership isn't the key driver, it's the 50% of our trade that is done with the EU that's the issue, combined with the markets worldwide that we penetrate off the back of EU collective agreements. The markets hate uncertainty and from the moment an exit vote is declared until the point when the trade agreements are signed with the EU and beyond, then that uncertainty remains.
we dont export 50% to the EU its lower than that, also we only export 12% of our total goods to the EU, so leaving will not hurt as much as you say it will