(dutchnews.nl)-- A vast proportion of foreign investment in the Netherlands leaves the country again through shell firms, according to new research by the national statistics office CBS. Last year, €4,587bn was brought into the Netherlands by what it called ‘special financial entities’ but 80% of that left again, the CBS said. Some 14,000 shell companies, or letterbox firms, are located in the Netherlands. Four in five carry out no economic activities and are used, in the main, to avoid tax, the CBS said. Last year, €3,665bn left the Netherlands, of which just over half was invested outside the EU. Asia and Oceania topped the list of destinations – mainly India, Hong Kong, China, Australia and New Zealand.