statistics – Two-choice party voting

Thank you for the comment suggesting that wasted votes might be compared the level of non-voting and informal votes.

Each of these statistics tells us something a little different.

Turnout (the inverse of non-voting) shows the level of engagement in the population. MMP elections have had turnout percentages between 74% and 88%, with the highest figure for the first such election. I’d interpret that high figure as indicating a high level of support for the new system.

The level of informal votes indicates, I understand, voters who wanted to make a protest of some kind, or who did not fill out the voting paper properly. For MMP elections that rate of informal votes ranged between 0.39% and 0.95%. The lowest figure was for the first MMP election. That suggests that voters did not have difficulty adapting the new voting paper. For later elections voters were less careful or more often wanted to make a protest.

I do not fully understand how spoiling a voting paper can be seen as a useful form of protest, but I understand that it is not uncommon.

Wasted votes for failing to meet a threshold fall into another category, one which is more directly associated with design of the voting system. These voters have gone to the trouble of voting. they had no way of knowing whether their preferred party would meet the treshold, but still their vote was disregarded. If the aim of a proportional voting system is to measure numbers of voters supporting different parties in government, then it is important that voters be able to support a party that may not pass the threshold AND have a say in the makeup of parliament.

Often, I’d suggest, people supporting minor parties are those with a strong interest in the political process, and perhaps in supporting new ideas. The threshold system without a second choice forces those people to either put aside their support for a small party OR risk taking no part in the deciding the makeup of parliament.

That is a difficult choice for someone with a strong interest in the political process.

Reducing the threshold only reduces the problem, it does not eliminate it, whereas the second choice eliminates the problem.

Here are the turnout and informal vote stats, transcribed from the election results website.

Election	Turnout %	Informal %
2020	82.24	0.73
2017	79.75	0.41
2014	77.90	0.45
2011	74.21	0.88
2008	79.46	0.51
2005	80.92	0.46
2002	76.98	0.42
1999	84.77	0.95
1996	88.28	0.39

Turnnout and informal vote stats for MMP elections. Manually transcribed from results site.

Small aside. We are very fortunate in New Zealand to have such easy access to stats like this. Reseaching other countries, it is often very difficult to find similar information.

I have created a report to show the party vote results for all nine MMP elections up to 2020, using a consistent format. The information comes from the official site electionresults.org.nz where the results of each election are provided but in various different formats. It provides for each party at each MMP election the number of party votes they received, the number of electorates won. My report shows which parties passed one or other of the thresholds (electorate seat won, at least 5% of party votes), and thus how many votes were wasted because parties did not pass either threshold.

The report can be seen here mmphistoryreport.pdf I believe that I have interpreted and transferred the data correctly.

From the report one can see:

That the wasted votes vary between 1.3% (2005) and 7.8%(2020), with an average of 5.4%.
The rate of wasted votes is very variable. It was very low in 2005 when there were many minor parties in parliament, many having won just one electorate seat. It was high in 2020, small parties having benefitted from a reduced National Party vote, without crossing a threshold.
The 2008 election would have been extremeely close between left and right leaning parties, had the threshold been 4% instead of 5%.
The larger numbers of wasted votes have generally been associated with a party gaining about 4% of the party vote, and thus having its votes wasted.
This suggests that the two choice system could reduce wasted votes from the present 5% to less than 1%. This is useful, but the main value of the two choice system is to reduce the risk of wasted votes, which is commonly seen as a real obstacle to voting for or working with small parties.

Tag: statistics

More on History of MMP election results

History of MMP results