Publications Office of the European Union
"How big is undeclared work in the EU? According to this study, more than 11% of work in the private sector is 'under the table'. However, there are big differences between EU countries, with Poland, Romania and Lithuania having the highest levels of undeclared work, while Germany and the Netherlands have low shares. The study analyses the reasons for this and examines the types of employments where undeclared work is more frequent."
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