keep it in one's pants vs make whoopee

keep it in one's pants

verb
  • To refrain from trying to have sex with someone. 

make whoopee

verb
  • To enjoy oneself in a boisterous manner. 

  • To engage in sexual intercourse. 

How often have the words keep it in one's pants and make whoopee occurred in a corpus of books? (source: Google Ngram Viewer )