How we managed before 1973 is quite irrelevant to 2019, dannyk13. The world is a quite different place.
Of course we will manage when we leave, but this thread is about how much worse off the EU will be and how much better off we will be when we leave, which is nonsense.
I can understand people voting to leave for all sorts of reasons, but "improved trade" is not one of them - and especially not if you have any care for the environment, as any improved trade could only be with countries who are a long physical distance from us when compared to the EU.