To create this chart, nationalist support is interpreted in the following manner: support for the Parti Québécois at the provincial elections of 1970, 1973, 1976, 1981, 1985, 1989, 1994, 1998. Support for the yes side in the two referenda on sovereignty in 1980 and 1995. Support for the no side at the referendum of 1992 on the Charlottetown Accord. The questions asked at the referenda, and fuller results can be found elsewhere on the site.
It is evident that not all voters who support the Parti Québécois are supporters of Quebec independence and are nationalists. Conversely, nationalists are known to have supported other parties such as the Union Nationale, the Ralliement Créditiste, the Action Démocratique du Quebec and even the Liberal Party at times. The data presented above should thus be read with caution.
Sources: Estimations made from various studies by Pierre DROUILLY, and especially an article in La Presse, December 5, 1998, p. B3; André BERNARD, Québec: élections, 1976, Montreal, 1976, Cahiers du Québec, HMH, 174p.; Daniel LATOUCHE, Guy LORD and Jean-Guy VAILLANCOURT, eds., Le processus électoral au Québec: les élections provinciales de 1970 et 1973, Montreal, Cahiers du Quebec, 1976, 288p., Rodrigue TREMBLAY, La Presse, December 4, 1998, p. B3. Pierre DROUILLY, Indépendance et démocratie, Harmattan, 1997, 355p.
My estimations are based on the results of the elections and the referenda with the hypothesis that no more than 7-22% of anglophones and allophones supported the nationalist party or cause. These are probably over estimations. Francophone population was estimated at between 80-82.5% over the period. Differentials in rates of voter turnout would also have to be factored in to arrive at more accurate results.