Duff vs Rod

Duff

name
  • A male given name 

  • An unincorporated community in Tennessee, United States 

  • An unincorporated community in Indiana, United States 

  • A village in Saskatchewan, Canada 

  • A surname. 

Rod

name
  • A nickname for the male given names Rodney and Roderick. 

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