For all the different polling questions being asked at the moment I prefer tracker questions which use the same format in the same way in poll after poll to get an historical picture of how things are developing. The best, as I repeatedly argue, are leader ratings which rarely get the attention they deserve often being ignored completely by the media outlets that commission them.
Unlike voting intention surveys which seek to establish what respondents might or might not do at an event more than three years hence leader ratings seek opinions which, of course, are what opinion polls are best at.
Deltapoll, the new name on the block founded a year ago by Joe Twyman, ex-YouGov, and Martin Boon, ex-ICM, has joined Ipsos-MORI and Opinium being part of a very select group of pollsters that carry out regular ratings of this form. Other firms may occasionally include a question but not on a regular basis so we can track the data. Each of them might ask a different leader rating question but they always ask one set of standardised question.
The Delta format is to ask the “well/badly” question and the past three laest surveys for TMay and Corbyn are featured in the chart above. Both have seen their net negatives get bigger since December but with Corbyn being it the hardest. The trend in with the other leader ratings pollsters is the same.
The question for Labour is whether and when this can be reversed.
Wikipedia has an excellent page where most, but not all, leader ratings are