Ladbrokes have a market up on the turnout at the next general election and I can understand why the 65% to 70% band is the favourite as it is the band at what turnout has been at every general election this decade.
If Boris Johnson is granted his desire and we have a December general election we will have a first general election in forty-five years that hasn’t been held in the April to June window. There’s a belief amongst some that this will have a negative impact on turnout but I have my doubts on this theory.
As we can see in the chart above of the turnout at general elections in the 1970s the turnout in February 1974 didn’t fall but increased by nearly 7% from June 1970, the October 1974 election saw turnout fall back but was still higher than June 1970.
I think the value might be in the highest band, 75% and over, because if Brexit is seen to be in danger (or being potentially stopped) I can see turnout surging as both sides rush to the polling stations to ensure their side ‘wins’. But this isn’t a market I’ll be betting heavily on at this time, when the date of the election and the status of Brexit on election day is confirmed then I’ll stake a bit more (odds permitting.)