How the German overhang and compensation system works

Heinz Brandenburg on Twitter walks readers through a very useful explainer on how the current Germany version of MMP deals with overhangs through a multi-layered compensation mechanism, and why it could mean the new Bundestag will top out at more than 800 seats!

It is best to read it in its native Twitter, but following is the text of most of it (courtesy of the ThreadReader app) . The starting point, not quoted here, is a poll of current party standing in the state of Bavaria.

[the remainder of this text is not mine, but Brandenburg’s; numbers correspond to tweets in the thread]


Last time around, the CSU won 38.8% of the vote but all of the constituencies in Bavaria (they even swept all of Munich). That results in so-called overhang and compensatory seats.
How are these calculated?

1/ Well, there are 93 regular seats allocated to Bavaria, 46 of which are constituencies. CSU winning them all meant 46 seats, but they only had 38.8% of the list vote or about 42% of the vote once you discount votes for parties that did not get into the Bundestag.

2/ 42% of the vote would mean their proportional share of seats was 39, not 46. So they got 7 Ueberhangmandate (overhang seats), i.e. 7 more seats than their proportional share.

3/ Since 2013, these seats have to be compensated for. So other parties get additional seats, to the extent that the 46 seats the CSU won amount to 42% of the total number of seats in Bavaria.
So Bavaria actually had 108 seats in the Bundestag, not 93. 

4/ But that is not the end of it. Bavaria’s 93 seats are proportional to its population size. If the state’s seat share increases to 108, then the 15 other states also need a larger share. And it wasn’t only Bavaria. 

5/ Baden-Wuerttemberg got 96 instead of 76 because of the CDU winning all constituencies, Brandenburg 25 instead of 20 because CDU won all but one constituency, Hamburg 16 instead of 12 because SPD won all but one constituency, and so on.

6/ What happens then is that to keep the 16 states’ share of seats in the Bundestag proportional, not only overhang seats within states need to be compensated, but overhang and compensatory seats within states have to be compensated across states.

7/ So North Rhine-Westphalia (NRW), the biggest German state, did not produce any overhang seats, because SPD and CDU are more evenly balanced there. But it got 14 compensatory seats, to make up for additional seats given to other states. 

8/ It is not a perfect compensation across states. Bavaria and Baden-Wuerttemberg have 15 and 20 seats, respectively, more than their normal share in the 2017 Bundestag. NRW only 14, despite being the larger state.

9/ Berlin, Niedersachsen and NRW were the only states where no overhang seats were dished out in 2017, largely a reflection of dominance of the CDU in a fragmenting party landscape. 

10/ CDU won all seats in five states, almost all seats in over a dozen states, despite having their worst election result in history, with 33%.

Could be very different this time around, with them down to 20% and the SPD at 25%. More states could get away without overhang seats.

11/ But one single state can make a big difference, and if the result in Bavaria is anywhere close to the recent polls (CSU 28%) it could be a dramatic effect.

12/ Even at 28%, the CSU would like win almost all constituencies. These are the four most marginal seats. Muenchen-Nord and Nuernberg-Nord are most likely to fall to the SPD. But the others are not certain.

So the CSU could still end up with 42-44 seats, on just 28% of the vote, or 31% if we remove votes for parties that do not get into the Bundestag.

14/ By my calculations, that would mean Bavaria’s seat share increases to 129 seats from their current 108 (and their nominal allocation of 93).

Once other states are compensated, that would get us to possibly 840 seats. 

15/ A few changes have been made, which I have taken into account – the first three overhang seats will not be compensated, which would keep Bavaria’s share at 129 rather than 135 under 2017 rules.

16/ And overhangs can also be compensated against a party’s list seats in other states. But I don’t think that applies to the CSU. They won’t take CDU seats away in other states to compensate for CSU over-representations.

17/ So one such lop-sided result, under increasing fragmentation – where suddenly 28% of the vote share allow a party to win almost all constituencies – can have incredible effects on the size of the Bundestag.

18/ The nominal size of the Bundestag is 598. This one result in Bavaria could increase the size of parliament by 40%.

No threshold for German MEPs

Apparently it is threshold day at F&V. While Israel may be raising its threshold, Germany will be dramatically lowering its. But only for its members of the European parliament (MEPs).

The Constitutional Court ruled in late February that the existing 3% threshold violated political parties’ rights to equal opportunities.

To the immediate question of why, then, the Bundestag (Germany’s elected chamber of the federal parliament) can have a 5% threshold–which was highly consequential in the most recent election–the Court has a ready answer: the role of the Bundestag is to sustain a government, and so limiting fragmentation is a valid interest. However, the European Parliament has no such role, and so it isn’t.

German president twisting in the wind

The presidency of Christian Wulff appears to be coming to an end. I found some of the language a little more elevated than one would expect from say discussion of the governor-gneral of Australia:

It is very difficult now to imagine how Wulff will exude the luminosity that I had hoped of him.

It does raise the question of how best to appoint and remove a ceremonial president. On the face of it comparing cases like Ireland where the president is popularly elected and Germany and Australia where the president is indirectly elected, indirect election does not always seem to work well. Since 1972 two governors-general of Australia (and 2 state governors) have been forced to leave early by public opinion. I am not aware of that happening with any Irish presidents.

Elections of 18 January

Two noteworthy legislative elections are being held today, in El Salvador and the German state of Hesse. Both are of interest not only for what will happen today, but also for what they signal about upcoming elections.

El Salvador

Today Salvadorans go to the polls to elect the 84-seat Legislative Assembly and municipal posts throughout the country. The main thing to watch will be, how big are the gains for the FMLN (the ex-guerrilla leftist political party)? The party currently holds 32 seats (38%), and as I noted at the time of the last legislative elections, the country’s electoral politics has been in stasis since the negotiated end of the civil war in 1994. Will this be the election that breaks the stasis? Maybe, but there is a major caveat.

The last legislative election, in 2006, was held in the month of March. In fact, every legislative election back to 1952 has been held in March (except in 1960, when they waited till April). For that matter, every presidential election under the current constitution (1983) has been held in March (with a runoff in April or May, when needed). So why are Salvadorans going to the polls in January?

Presidential terms are five years and legislative terms three years, and so they will occur in the same year every 15 years. The last time elections to the two branches occurred in the same year–math whizzes will have recognized already that that was in 1994–they were on the same day in March. And therein lay a problem for the Salvadoran right.

The FMLN has been leading the polls in advance of this year’s presidential race for many months. To ward off a possible coattail effect, the center-right parties that control the legislature and presidency de-coupled the elections. So instead of a concurrent contest, El Salvador will have what I refer to as a “counterhoneymoon election” today. A legislative election shortly before a presidential election provides voters and party leaders with information, as CNN says in the opening paragraph of its news story on the elections:

El Salvador will elect more than 340 local and congressional officials Sunday, two months before the nation’s presidential election. But Sunday’s results could go a long way toward determining who that next president will be.

Well, actually, I think we already know–barring surprises–and as I suggested above, that’s precisely why these elections are today. But the general point is that these elections will either show the left as being more vulnerable than opinion polls and pundits suggest, or they will show the right what options it has to turn the tide by March.

It would be a surprise if the FMLN won a majority of seats today. It just might have had a shot at a majority (or close to it) had the legislative elections been left concurrent with the presidential race. But I would regard anything short of 39 seats for the FMLN as a victory for the right. Why 39? Because that is the highest seat total any party has won since the FMLN began competing in elections. More importantly, 39 was the total won by the long-ruling ARENA in 1994–in a concurrent election in which the ARENA presidential candidate won easily (49-25% in the first round, 68-32 in the runoff). That sort of presidential “pull” is exactly what ARENA wanted to prevent the FMLN from getting this time around.


The results of this election are already in, and the Christian Democratic Union (the party of federal PM Angela Merkel) has won “handily.” DW reports:

Near-complete returns show Merkel’s CDU, lead by Roland Koch, narrowly increasing their share of the vote to around 38 percent. The SPD suffered dramatic losses, slumping more than 13 percent to a historic low of just over 23 percent. Among the smaller parties, the liberal Free Democrats took 16 percent of the vote, their best result in Hesse in more than 50 years. The Greens had 14 and the Left Party five percent respectively. The CDU says it now hopes to form a coalition government with the FDP. Voter turnout was low at just 60 percent.

This election is of greater interest than a state election normally would be for two reasons. First, federal elections are due later this year, and this is one of the last states to be voting before the national electorate will go to the polls.1 With both the CDU (accompanied by its Bavarian partner, the Christian Social Union) and its partner in the federal “grand coalition,” the Social Democrats (SPD), less than eager to continue the current arrangement, this state result is a potential bellwether.

The second item of interest in this election is that the state had been to the polls just under a year ago. In the 2008 election, the CDU and SPD each had won 42 seats (out of 110) and the Left (based on a union of ex-communists with leftist who had split from the SPD) had a breakthrough, winning 6 seats. The Greens had 9 and the FDP 11. This result meant no majority for either a center-left or a center-right coalition unless the center-left coalition included the Left party.

Following the 2008 election, coalition bargaining took some time and ultimately produced a formula in which the SPD and Greens would govern with the outside support of the Left. Never mind that the SPD leader, Andrea Ypsilanti, had explictly promised in her campaign not to work with the Left. It was the only possible majority unless the Greens, CDU and FDP would work together (which was also discussed, but failed). And then the SPD caucus vetoed Ypsilanti’s plan. That display of unwillingness of the SPD to set the precedent, in the old West Germany, of cooperation with the Left set the stage for this re-run (with a new SPD leader).2

The CDU has to feel pretty good about its chances in the federal elections after waiting out the center-left divisions in Hesse.

1. There will also be elections in Brandenburg, Saarland, Saxony, and Thuringia on 30 August. Federal parliamentary elections will be 27 September.

2. This summary is based primarily on my recollections of coverage over several months at DW-TV’s Journal. See also the brief summary from AFP.