A Brief History of Elections III: SDP

Everyone is interested and excited about how the opposition would fare in the next elections. At least coming from someone who can’t vote and is an observer. It is extremely difficult to predict how people vote, because last-minute issues can pop up and turn the tide of the supposed winner. But at the same time, assuming there’s no such Black Swan event, there is a small amount of certainty we can predict how people cast their votes, by speculating on their motivations, the context – and a little bit of history.

Since there’s no straw poll to see which party has the most amount of goodwill or support, we’ve to look at past performances to peer into the future. I’ll do these in a few ways: 1) percentage of popular votes, 2) percentage of total parliamentary seats contested, 3) percentage of votes in contested wards. I’ll elaborate later. Have a look at the first graph of this post:

Share of popular votes in %. Source: Singapore Elections

* The results of SDA in 1997 are from SPP, the party which Chiam See Tong founded after leaving SDP. The results of NSP are the same as SDA in 2001 and 2006 because NSP was a major component party in SDA.

As my post suggests, I’ll be looking at the SDP (the yellow bar). Between 1988 and 1997, they were ranked third in terms of popular vote share, or the second best-performing opposition party. In 2001, they emerged second in popular vote share, but this is due to the WP’s exceptionally poor performance. In the last elections, they were ranked bottom.

Why does popular vote share matter? Seeing how the parties score is an indicator of their support across the country (hmm, at least in contested wards). By ranking the PAP and the major opposition parties, a pattern can emerge that suggests which party S’poreans prefer, elections after elections. As you can see, the popular vote share of the SDP has been shrinking over the past 5 elections. This graph is actually flawed, as no opposition party has put up candidates in all wards. If all the opposition parties and the PAP fight in every ward i.e. each ward having a 4-way fight, the popular vote share graph would be more accurate in terms of gauging voter support.

But this is still useful – see which party is most consistent. And from the graph, SDP has been consistent in the wrong sense, that its popular vote share is on a gradual decline. The next elections seem to be bust or boom for them – either they continue their decline (below 8 percent), or they jump to the 10-odd percentage points of the popular vote share. It took the NSP (first elections 1988) four elections to increase their popular vote share beyond 10 percent, and even then, as one of the two major component parties of the SDA. The SDP, with a longer history, should have it easier to reverse their decline.

Absolute no and % of seats contested. Source: Singapore Elections

This graph shows the absolute number and percentage of seats which SDP has contested in the past elections. Why is this important? Well, obviously the opposition party’s goal is to form the next govt, and expanding their presence in Parliament is the first step to projecting their influence. Ideally, a party’s number and percentage of seats contested should increase, suggesting it is increasingly confident of challenging the ruling party. And the number of seats contested shows how many candidates it can find, which means if the party is able to retain its core members or find new ones.

For the SDP, their absolute number and percentage of seats contested has been on a descending trend. Ironically, the sharp drop in seats contested in 1991 coincided with the election of 3 candidates. As the first graph on popular vote share corroborates, the SDP is on a decline; decreasing support from voters, and smaller percentage of total seats contested.

% of votes in contested wards vs. popular vote share. Source: Singapore Elections

The red line here represents the percentage of votes in SDP-contested wards. That means, if we combine all the wards which SDP contested to form one entity, we can calculate the percentage which SDP scored only in its contested wards – unlike the first graph, where popular vote means including votes from wards which SDP did not contest.

Hence we are seeing a micro picture of PAP vs SDP (there might be 3-cornered fights, but the results of the third party should be minute). The SDP’s percentage of votes peaked in 1991, where it won a handsome 3 seats, but from then on, it has been on a decline too. In other words, it is doing quite badly against the PAP, if the wards which it contested represents S’pore, and there were only two parties, the PAP vs. SDP. As I mentioned, it seems to be going bust.

Now, for something interesting:

% of seats contested vs. % of votes in contested wards. Source: Singapore Elections

In 1991, where the percentage of seats which SDP contested fell, and in absolute number, only 9, the percentage of votes it received in contested wards was 48.6 percent. When it fielded a slightly larger number of candidates, its percentage of votes fell instead. This can be attributed to both SDP weaknesses and PAP strength. But one lesson from this statistic is that a party can still do well in its contested wards, even if it fields a small number of candidates.


If I use the above graphs to predict the SDP’s performance, they would probably do very badly. However, they are active in the new media, and recently presented their Shadow Budget. And from a glance at their website, they seem to be strong and confident. Whether voters will give them a chance to reverse their decline is another question, to be answered soon.


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