Labour and Conservative Decline Traces Back Over Half a Century

This morning I posted about the decline in the overall share of the two “major” parties and how this pointed to a certain hung parliament.

The post attracted a lot of traffic and several comments not least from one Ben Goldacre, journalist, doctor and author of the Bad Science blog.  I used ICM/Guardian data and plotted a graph showing the decline in votes over the last 20 years for the two major parties. He accused me of bullshitting and repeatedly called me a twat because I had omitted data from 1984-1990 that was available from the Guardian.  In fact the reason for starting from 1990 was because 20 years seemed like a good length of time to support the argument and there was a blip in the early eighties caused by the split of the SDP from Labour and their alliance with the Liberals.  I ought to point out that I wasn’t entirely blameless in the exchange in that I suggested he’d had a drink or two. Sorry Ben.

I am now posting using election data from the last 50 years and the latest poll data for 2010.  I think the picture is pretty clear and undistorted and supports the earlier hypothesis.  The combined support for the two main parties has been falling for 50 years.  If that continues and there is no proof that it will then two-party politics is on the way out.  The defining moment might just be on Thursday.

‘Hung’ Parliament Guaranteed by Labour and Conservative Decline

The TV debates aren’t responsible for the Hung Parliament that will follow Thursday’s election as surely as night follows day.  A quarter of a century of decline in the combined Labour and Conservative share of the vote means that the two party stranglehold over UK politics is on its way out and Clegg’s TV performance was just a tipping point.

One of the wonderful things about the web is the accessibility of data.  The Guardian has published all of the Guardian/ICM polling data since 1984. At Election 10 we took the combined Labour and Conservative share for every poll and created the graph above.  In 1990 the two parties were claiming almost 90% of the vote between them this has shrunk to a little over 60% and it has been a steady consistent decline.   A continuation of this would mean a government taking power that was opposed by around 65% of the population.  Even our bizarre electoral system can’t sustain this.

To predict the future we must delve into the past.  In this case the past is telling us that the party is very nearly over for the reds and blues and the voters will be calling time this Thursday.