Presumably you are talking about the UK not benifiting and not these other EU nations? If so, what is all this data below about? I replied to your post with it about 10 pages backwhen you asked for hard data, did you evaluate it? What were your thoughts? Is it gonads or not applicable to everyone in the UK? Maybe fair points if backed up.
From the FT:
Britain joined what was then the European Economic Community in 1973 as the sick man of Europe. By the late 1960s, France, West Germany and Italy — the three founder members closest in size to the UK — produced more per person than it did and the gap grew larger every year. Between 1958, when the EEC was set up, and Britain’s entry in 1973, gross domestic product per head rose 95 per cent in these three countries compared with only 50 per cent in Britain.
After becoming an EEC member, Britain slowly began to catch up. Gross domestic product per person has grown faster than Italy, Germany and France in the more than 40 years since. By 2013, Britain became more prosperous than the average of the three other large European economies for the first time since 1965.
Data compiled by Rebecca Driver of the consultancy Analytically Driven highlight a causal link between Britain’s greater openness to trade since 1973 and its subsequent specialisation in high productivity sectors, including finance, high-tech manufacturing and business services. Ms Driver said the 11 per cent of British companies that trade internationally are responsible for 60 per cent of the UKs productivity gains
“These companies prefer large geographically concentrated markets with strong unified regulations,” she adds. “For the UK, that is the EU”. In other words, trade drives competition and growth. Since 1993, the UK has been the bloc’s top recipient of inward foreign direct investment, according to the UN. .
https://www.google.co.uk/amp/s/amp.ft.com/content/202a60c0-cfd8-11e5-831d-09f7778e7377
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The GDP value of European Union represents 26.45 percent of the world economy. You'd still say its no powerhouse tho?
Academia, economists and simple logic shows that having free trade with 500 million people helps the UK. Impairing that trade and losing any input into the terms of that trade is a bad thing. Yes the UKs success has come at a cost. We’ve had migration which has put a strain on some communities and maybe we focus too much on wealth creation over society, but I believe both these things can be addressed by OUR government, it’s all too easy to blame the EU for all of our internal issues.