convenience vs public convenience

convenience

noun
  • Any object that makes life more convenient; a helpful item. 

  • The quality of being convenient. 

  • A convenient time. 

verb
  • To make convenient 

public convenience

noun
  • A lavatory that is provided for public use, i.e. use by any person. 

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