I do love a bit of data me, so I'll just leave this here, I went to the fairly anti immigrant Migration Watch website to do this.
for the last few years net migration from the EU 14 countries (65% degree level workers and likely to be in higher level jobs) is far higher than net migration from the EU 8. In fact net migration from the EU14 in the for the last two years ending Sept 2015 was 80,000 and net migration from the EU8 was 42,000, down from a height of 87,000 in 2007.
Basicaly what this means is that far more people from the EU8 return home after a few years of living and working in the UK than from the EU14, but also that a lot of people from both return home.
Now the Telegraph (using my previously mentioned University of Oxford Migration Observatory data) estimates the no of EU 8 workers in the UK to be 942 000 which is 1.2 % of the population. The number of retired peope in the UK is 10 million equating to 15% of the population. So really we are getting to a situation where we need immigration to support the growing number of retired people, National insurance payments are not hyptothecated and therefore we need more people working in order to support the growing retired generation.
Secondly, the OUMO (as cited above) says that most immigrant workers of all kinds but especially of the EU8 and EU2 are likely to be younger and therefore not have families, and as they are likely to go home, your example family is going to be a very small % of any of these groups. Previously as stated the UCL study found that EU migrants make a positive fiscal contribution.
The notoriously conservative (note the small c) Ecomomist using data from the BOE as well as Goldman Sachs, Citigroup, HSBC etc also think that the long term economic effects of Brexit in terms of trade and the UK current account will be "adverse", especially as studies show that EU membership has helped UK economic growth greatly (well it would seeing as a regularly agreed 45% of our exports go there)
It also says: " Norway and Iceland have access to the single market through their membership of the European Economic Area (EEA). But they are obliged to observe all the EU’s single-market regulations without having a say in them, to make payments into the EU budget (in Norway’s case, around 90% of Britain’s net payment per head) and to accept free movement of EU migrants"
AND even to further the point that while Canada and others who while having to abide by product regulations do not have to accept migration, they have a far smaller percentage of exports to the EU as 78% of Canada's exports go to NAFTA countries. those deals do not include financial services and other very important industries to the UK's balance of payments.
The EU is the largest trading bloc in the world, within it we have access to 52 trade deals that are on going ( TTIP is another matter I don't back it) but outside it we are weaker in negotiationg points with all of these other markets, this does not benefit British business.
As was said about Scottish independence, stronger within, weaker without, the same goes for the UK with the EU.
So, then my data comes from, the OECD, OUEO, Telegraph, Economist, UCL, Migration watch, where is yours from?