Nigger vs Tan

Nigger

name

  • A given name for a black pet. 

  • Niger (country). 

Tan

name

  • A Chinese surname from Hokkien. 

  • A surname from Vietnamese. 

  • A Chinese surname from Mandarin. 

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