lunatic vs maniac

lunatic

noun

  • An insane person. 

adj

  • Crazed, mad, insane, demented. 

maniac

noun

  • An insane person, especially one who suffers from a mania. 

  • A fanatic, a person with an obsession. 

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