Disproportional Outcome despite PR: The 2013 German Federal Election

by Steffen Zittlau & Thomas Gschwend, University of Mannheim

What is the story?

The federal election that took place last Sunday (September 22) in Germany has produced a clear winner, the conservative CDU/CSU. Although the party received 41.5% of the votes, it falls short of obtaining an absolute parliamentary majority by 6 seats out of the 630 of the Bundestag. The remaining seats were obtained by the three leftist parties (the SPD, the Greens, and the Left). A leftist government is however unlikely to be formed since the SPD and the Greens explicitly mentioned before the election that they would refuse to govern with the socialist Left. Possible government coalitions are thus CDU/CSU-SPD or CDU/CSU-Greens (see here)

That the CDU/CSU would do well in the election was expected: Germans were relatively satisfied with their government’s performance, and the party leader Chancellor Merkel enjoyed a historically high popularity. During the campaign, the possibility that the conservative party obtains a majority of seats was totally overlooked by political commentators. The German electoral system relying on proportional representation (PR), nobody imagined that this would be possible. As a matter of fact, it actually occurred only once in the political history of post-war Germany, in 1956. Yet estimations show that 43% of the votes would have been sufficient for the CDU/CSU to gain an absolute majority. During the election night, early projections even predicted the party to reach this threshold. In this entry, we explain how a proportional representation electoral system may lead to such an unusual result.

The importance of wasted votes

The reason why 43% of the votes would have been sufficient for the CDU/CSU to obtain a majority of parliamentary seats is the exceptionally high number of votes that were wasted on parties that gained no representation in parliament. Two parties only narrowly failed to gain representation in the parliament due to the 5% electoral threshold: The pro-business liberal FDP (4.8%), and the new anti-Euro single-issue party, Alternative for Germany (AfD, 4.7%). There will more on these parties in upcoming entries. Additionally, the vote share received by all other small parties reaches about 6.3%. In total, 15.8% of all the votes were effectively wasted as they found no representation in the parliament. This is a record for post war Germany and, certainly one of the highest scores among countries using a PR electoral system.

Vote-Seat disproportionality in Germany

The figure below shows how exceptionally disproportional the election was: The 2013 election reaches 8.6 on the Gallagher disproportionality index (Gallagher 1991, data from here). The Gallagher index is bounded between 0 and 100, where higher values represent more disproportional electoral systems. 8.6 is higher than for elections in Spain (e.g. 2011: 6.93; source), which is known to produce most disproportional outcomes due to low district magnitude (see Figure below)


The mean value for the 17 preceding German elections since 1945 is only of around 3, which is largely in line with other countries using PR (Belgium 2010: 3.77, Switzerland 2011 3.75). Though this disproportionality remains lower than for most elections organized under plurality electoral system (such as in Canada, in 2011: 12.42; or in the UK in 2010: 15.50), it is worth noting that this index was of 3.14 for the 2010 US Congressional election.

PR does not always guarantee proportional results

This election shows that PR electoral systems are no insurance against disproportional election outcomes. The presence of a relatively high electoral threshold, a large number of parties, and the failure of voters to coordinate their votes between the parties opens the risk of a substantial vote-seat gap. More importantly, this disproportionality raises concerns about the overall representativity of the parliament (see also Powell & Vanberg 2000). In this election, the rightist parties (CDU/CSU, FDP, AfD) would have had a clear parliamentary majority if the 5% threshold would have not existed.

What lessons can be learned?

In elections, parties first and foremost try to maximize the number of votes and seats they receive. In PR electoral systems, however, they should also consider post-election bargaining. In particular, they should make sure their coalition obtains a majority of parliamentary seats. The CDU/CSU failed to do so. If 0.2% of CDU/CSU supporters would have cast a ‘rental vote’ (on the concept of rental vote, see this previous blog entry) for the junior coalition partner FDP, the CDU/CSU could now easily form a majority government without compromising too much on the agenda they campaigned on. Given the ultimate results, the CDU/CSU will have to offer many painful concessions to get either the Greens or the SPD to sign a coalition agreement. Either way, these concessions will be very costly in terms of policy orientation. Also the number of ministries held by the CDU/CSU in a coalition with the SPD for instance would be way smaller than the number it would have got in a coalition with the FDP.

Thus, let’s not forget one important characteristic of PR electoral systems: The winner of an election is not necessarily the one who gains the most votes or even the most seats!

Follow us on Facebook and Twitter.

This entry was posted in Blog. Bookmark the permalink. Both comments and trackbacks are currently closed.