With opinion polls showing dazzling range - from Leave being 4 points ahead to Remain 13 points ahead - it's worth looking at the betting markets. The below is a live chart, which will update every time you revisit this page. It updates several times throughout the day.
At the time of writing, the graph underlines a basic point about referenda: no matter what the polls say, the status quo has a huge in-built advantage. Or, at least, a lot of people are betting that voters will stay with the status quo.
Mind you, this time last year, the betting markets gave David Cameron a 10pc chance of winning a majority. Greater than the 0.5 per cent chance given to him by Populus (and I know it's unfair to single out Andrew Cooper, as his firm simply predicted, as a percentage, what other polls implied) but everyone was pretty wide of the mark. Let's see if the pollsters, pundits and bookmakers do any better this time.