airing vs press conference

airing

noun
  • The broadcast of a television or radio show. 

  • A public expression of an opinion or discussion of a subject. 

  • An exposure to warm or fresh air. 

press conference

noun
  • A question-and-answer session with members of television, print and other media. 

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