Libertarian vs Socialist

Libertarian

adj
  • Of, or pertaining to, a Libertarian Party. 

noun
  • A member of a political party or movement that uses the term "Libertarian" in its name (e.g., the Libertarian Party of the United States); one who is likely to support policies that are libertarian. 

Socialist

adj
  • Of, belonging to, or constituting a party or political group that advocates socialism. 

noun
  • A member of a party or political group that advocates socialism. 

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