(key) player vs leading lady

(key) player

leading lady

noun
  • A woman who does or can play the lead role in a movie, play or other production; a woman who frequently plays such roles. 

  • The type of conventionally beautiful and approachable woman who is perceived as being capable of playing female lead roles in movies or other productions. 

How often have the words (key) player and leading lady occurred in a corpus of books? (source: Google Ngram Viewer )