American football vs handegg

American football

noun
  • A game similar to rugby football played on a field of 100 yards long and 53 1/3 yards wide (with two 10 yard-long endzones) in which two teams of 11 players attempt to get an ovoid ball into each other's territory. 

handegg

noun
  • The ball used to play such a game. 

  • Any of the sports that are called football but are played mainly with the hands and with a prolate spheroid ball; that is, American football and (less often) Canadian and Australian football. 

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