Dataset of Electoral Volatility in the European Parliament elections since 1979

[An updated version is available at http://dx.doi.org/10.7802/1905] This dataset provides data on electoral volatility and its internal components in the elections for the European Parliament (EP) in all European Union (EU) countries since 1979 or the date of their accession to the Union. It also provides data about electoral volatility for both the class bloc and the demarcation bloc. This dataset will be updated just after May 26, 2019, so as to include the 2019 European Parliament elections. [An updated version is available at http://dx.doi.org/10.7802/1905] This dataset provides data on electoral volatility and its internal components in the elections for the European Parliament (EP) in all European Union (EU) countries since 1979 or the date of their accession to the Union. It also provides data about electoral volatility for both the class bloc and the demarcation bloc. This dataset will be updated just after May 26, 2019, so as to include the 2019 European Parliament elections.