Referendum Record Points to Scotland No: Chart of the Day

Scottish nationalists pressing for a Yes to independence in a referendum one month from today can add historical precedent to opinion polls that suggest the campaign to keep the U.K. intact will prevail.

The CHART OF THE DAY shows analysis by Alan Renwick of Reading University of voting patterns in 34 referendums since 1980, on topics from constitutional reform to independence. It shows an average swing of 11.7 percent toward the certainty of the status quo in the month before ballots are cast.

With little more than four weeks until the Sept. 18 vote, the Scottish National Party’s pro-independence campaign has the support of 32 percent of voters compared with the No campaign’s 45 percent, a monthly TNS poll of 1,003 voters showed Aug. 13. Among those certain to vote, the gap narrowed to 8 percentage points with 16 percent undecided.

“The volatility tends to be in one direction and it’s fairly predictable,” said Renwick, whose analysis will appear in Sex, Lies and the Ballot Box, to be published in October. “We can see clearly why some referendums don’t follow the pattern, and those reasons are not going to be strong in the Scottish referendum, partly because it’s very clear that uncertainty is greater if you go for independence than if you don’t.”

The SNP campaign’s emphasis on the things that will remain in place if people vote to end the 307-year-old union, including the pound and European Union membership, is part of an attempt to reassure those put off by fear at the uncertainty of change, Renwick said. By contrast, the No campaign has stressed independence as a “leap in the dark.”

A switch to “Yes” has occurred in votes where the status quo was successfully painted as unsustainable, including in 1994 when voters in Austria, Finland and Sweden were persuaded that remaining outside the EU was no longer an option. In New Zealand in 1992 voters wanted to send a message of dissatisfaction with a political establishment united against change and knew a yes vote would not be binding. It’s difficult to argue that either case applies to Scotland, said Renwick.

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