Diagram showing the distribution of seats in the European Parliament by political group (1979).

Diagram showing the distribution of seats in the European Parliament by political group (1984).

Diagram showing the distribution of seats in the European Parliament by political group (1989).

Diagram showing the distribution of seats in the European Parliament by political group (1994).

Diagram showing the distribution of seats in the European Parliament by political group (1999).

Diagram showing the distribution of seats in the European Parliament by political group (2004).

Diagram showing the distribution of seats in the European Parliament by political group (seventh legislature: 2009–2014 — incoming Parliament).

On 20 September 1976 in Brussels, representatives of the Member States of the European Communities adopt the Act concerning the election of the representatives to the Assembly by direct universal suffrage.

Consolidated version of the Act of 20 September 1976, as last amended by Article 5 of the Treaty of Amsterdam.

Consolidated version of the Act of 20 September 1976 concerning the election of the Members of the European Parliament by direct universal suffrage, as last amended by Council Decision 2002/772/EC, Euratom of 25 June and 23 September 2002. The Act stipulates that the term of office for Members of the European Parliament is five years (Article 5).

European Council Decision of 28 June 2013 establishing the composition of the European Parliament.