Here is a long overdue update of my UK opinion poll tracker and in this post, I going to take a closer look at the key trends over the last 12 months.
National Overview
The most notable point about chart G1 has been the steady drift downwards for the Labour party following their poll spurt in the immediate aftermath of the 2017 General Election. The Conservatives on the other hand seem to be fluctuating around 40%.
The net effect is that both Labour and Conservatives have lost 3 points since the last election with voters switching to all of the minor parties..
Poll Movements Over Last 12 Months
This is a new section for my poll tracker where I take a closer look at trends over the last 12 months. My goal is to discern any patterns that could be a portent of the future.
Chart G4 shows daily movements and by eye, I can see 5 distinct periods labelled A, B, C, D & E. The exact dates of these periods are shown in table G6 later. Chart G5 has also been divided into the same 5 periods and this chart shows the Conservative lead over Labour. Briefly, the 5 periods can summarised as follows:-
- A – A quiet period in the polls with little happening. At most a small drift from UKIP to the Conservatives allowing them to close the gap on Labour.
- B – An anti-semitism controversy flares up in Labour which hits their poll ratings with some Labour voters defecting to the Lib Dems. The Conservatives take a lead over Labour.
- C – In the aftermath of the local elections, the Conservatives maintain a 2 point lead over Labour.
- D – The Chequers Brexit deal is announced and the controversy costs the Conservatives 3 points and Labour briefly regain their lead. UKIP are the main beneficiaries of the Conservative defections.
- E – Another anti-semitism controversy flares up in Labour which costs them a point. The Conservatives make a slow recovery and the net effect is their 2 point lead is restored.
For the Conservatives, the last 12 months is probably as good as they could have expected given the dominance of the Brexit negotiations in the news. 
Overall they have basically arrested the slide in their vote that they saw in the 6 months after GE17. Labour has been on a steady downward drift with notable fallbacks in periods B & E which I associate with the anti-semitism controversies that arose at those points in time. For the Conservatives, the Chequers deal period D saw their lead briefly eliminated but they have now recovered.
All of the smaller parties have been able to recover some voters since the general election but fundamentally the polls are not greatly changing given all the political events going on. I would say Labour should be the most concerned as they do now appear to be on a downward drift with the Lib Dems, Greens and Others (mostly Nationalists) picking up the defectors. Thus we could see the Conservative lead over Labour slowly widen.
Voter Switching Patterns
I will update this section in a later post.
Brexit Vote Dynamics
I will update this section in a later post.
Regional Trends
Following the 2017 general election, I analysed why my forecast was in error by such a large margin. I was able to show that the key error was that the opinion polls were not uniform in their underestimate of the Labour vote. In the South and Scotland, the polls were broadly in line with the final results and my forecast was not that far out. However, in the North & Midlands the error was considerable which had a dramatic effect on my forecast.
Given this error, it will be a while before I decide to update this section.
Voter Demographics
I have no update to give this month. If you are interested in the question of whether there was a “Youthquake” in the 2017 General Election and what the effect of allowing 16 & 17 year olds to vote, then please read my Opinion Poll Tracker of March 2018.
More Posts about Opinion Polls
Since the 2017 General Election when my forecast was undermined by yet another polling failure, I have written a number of posts about the long term accuracy of opinion polls and these are listed below:-
- How accurate are the opinion polls in the UK?
- Who is the most accurate pollster in the UK?
- Do UK pollsters show forecasting skill?
- My Welsh Barometer Poll forecast was a success!
To see my previous Opinion Poll Trackers, please click the relevant month below.
