Conservative vs Progressive Conservative

Conservative

noun

  • A member or supporter of the Conservative Party of Canada, or its predecessors, or provincial equivalents, or their predecessors 

  • pertaining to Conservative Judaism 

  • A member of the Conservative party. 

Progressive Conservative

noun

  • A member of the Progressive Conservative Party of Canada. 

adj

  • Pertaining to the Progressive Conservative Party. 

How often have the words Conservative and Progressive Conservative occurred in a corpus of books? (source: Google Ngram Viewer )