These figures have been calculated on the basis of a method which is still under development and are therefore provisional. The size of online purchases by Dutch consumers in foreign EU webshops is calculated on the basis of VAT declarations. Filing VAT returns in the Netherlands is compulsory for companies selling products to Dutch consumers from other countries, with a threshold amount of 100 thousand euros in annual turnover. It is not compulsory for those companies with an annual turnover in the Netherlands which falls below this amount. With the VAT returns as a source, it is possible to collect data on the foreign webshops visited by Dutch consumers. Since webshops with low turnover are not required to file VAT returns in the Netherlands, the total amount spent by Dutch consumers in European webshops is underestimated. CBS is unable to provide an indication of the size of this underestimation.