In Europe, road crash costs range from 0.4% (Ireland) to 4.1% (Latvia) of the gross domestic product. With 2.2% (€ 17 billion in 2018) the Netherlands is one of the countries with relatively high costs (see SWOV fact sheet Road crash costs). Wijnen et al.   observe that the differences in road crash costs between European countries partly depend on the calculation method used. Countries that use the so-called ‘willingness to pay’ method (the amount people are willing to pay for a certain crash risk reduction) report substantially higher cost estimates than countries that do not use this method . In calculating crash costs, four European countries (the Netherlands, Norway, Sweden and Switzerland) also take unreported crashes into account, while 17 other European countries do not  . See SWOV fact sheet Road crash costs for more information about these costs in the Netherlands and elsewhere.