We’ve reached another symbolic marker in the countdown to the election. There are now just 200 days to go.
The very latest opinion poll, published overnight by YouGov, puts Labour on 35%, the Tories on 32%, Ukip on 16% and the Liberal Democrats on 7%.
Were this reflected come the general election on 7 May, on a uniform swing Labour would form a government with a majority of around 30 seats.
This is roughly what the polls have been suggesting for the past few months. With just 200 days to go, is it time to start treating these polls not merely as snapshots but more like forecasts?
I’ve taken a look back at the last five elections to find out.
Two polls were published exactly 200 days before the 2010 election. The graph below shows, on the left, the average of these two polls (one by ICM for the Guardian, one by Ipsos-Mori), and on the right the actual election result:
It’s useful to be reminded of just how far the Tories’ share fell during this period: a total of eight percentage points. Labour also fell, but by just one point. 2010 was a rare example of both main parties losing support in the run-up to an election. The chief beneficiary was the Liberal Democrats, but ultimately only by four points.
Despite these changes in share, you can see that all three parties retained the same ranking of first, second and third place.
But the Tories’ share fell from one that would have given them a majority to one that did not: something I’m not sure many were anticipating 200 days before polling day.
No polls were published precisely 200 days before the 2005 election, so I’ve used the nearest: a survey by ICM for the Guardian on 24 October.
2005 represents the most static of all my 200-day comparisons.
The closest poll 200 days before the 2001 election was done by Mori for the Mail on Sunday on 25 November 2000. And in this instance, there were some notable changes between the poll and the election result:
Labour’s share fell six points while the Tories’ fell by two: another example of both main parties shedding support. The Lib Dems did well, picking up five points. But Labour’s lead was always big enough to ensure the outcome of this election was never in doubt – as was the case in…
On this occasion the nearest 200-day poll is only one day out, dating from the 14 October 1996. It was conducted by Mori and put Labour on a lofty 53%. This would fall by 10 points come polling day:
Over the same period the Tories only picked up one point, while the Lib Dems once again added five. It’s rather startling to look at an example a party polling not just over 40% but over 50%. I don’t think we’ll see those days again for while.
Here’s the only example in the past 25 years of parties changing positions in the polls from 200 days ahead of a general election.
On 23 September 1991, the Tories and Labour were tied on 40%. 200 days later, Labour had dropped six points and the Tories had risen by two:
But this is the exception to the pattern. 1992 aside, in every case the party in front in the polls 200 days before an election was still in front come the big day. Whether this pattern still applies depends largely on whether you think the polls will move a great amount between now and 7 May 2015. I tend to think they won’t. What I do think is that we’ll continue to see movement of a small amount. And with Labour and the Tories so close, even a tiny change could affect the chances of either party.
It’s going to be a tantalising 200 days.