go down vs happen

go down

verb
  • To take place, happen. 

  • To crash. 

  • To be soundly defeated. 

  • Used other than figuratively or idiomatically: see go, down. 

  • To be received or accepted. 

  • To be pleasant, etc., when eaten or drunk. 

  • To perform oral sex. 

  • To decrease; to change from a greater value to a lesser one. 

  • To fall (down); to fall to the floor. 

  • To sink. 

  • To be blamed for something; to be the scapegoat; to go to prison. 

  • To stop functioning, to go offline. 

  • To be recorded or remembered (as). 

  • Synonym of set, to disappear below the horizon. 

happen

verb
  • To occur or take place. 

  • To do or occur by chance or unexpectedly. 

  • To encounter by chance. 

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