American football vs Called football in the United States and Canada and American football elsewhere in the world

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. 

Called football in the United States and Canada and American football elsewhere in the world

How often have the words American football and Called football in the United States and Canada and American football elsewhere in the world occurred in a corpus of books? (source: Google Ngram Viewer )