This dataset provides data on electoral volatility and its internal components in parliamentary elections (lower house) in 20 countries of Western Europe for the period 1945-2023. It covers the entire universe of Western European elections held after World War II under democratic regimes. Data for Greece, Portugal and Spain have been collected after their democratizations in the 1970s. Altogether, a total of 347 elections (or, more precisely, electoral periods) are included.
When several elections were held in a single year, the data for the last election is included in the QoG dataset.
This dataset identifies and lists all the new parties emerged in Western Europe since 1945 and provides data about party system innovation, defined as the aggregate level of 'newness' recorded in a party system at a given election. Data are based on parliamentary elections (lower house) of 20 Western European countries since 1945. This dataset covers the entire universe of Western European elections held after World War II under democratic regimes. Data for Greece, Portugal and Spain have been collected after their democratizations in the 1970s.