Ken vs Rob

Ken

name
  • A diminutive of the male given name Kenneth. 

  • Kensington in London (in combinations, e.g. South Ken, High Street Ken). 

  • A surname. 

Rob

name
  • A diminutive of the male given name Robert. 

  • A surname transferred from the given name, derived from Robert. 

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