bughouse vs nuthouse

bughouse

noun

  • A hospital, especially a lunatic asylum. 

  • A flea-infested hotel, lodging-house etc. 

  • A prison. 

  • A cheap and dirty cinema. 

adj

  • Crazy, insane. 

nuthouse

noun

  • A hospital for the mentally ill. 

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