Tad vs Tan

Tad

name

  • A diminutive of the male given name Thaddeus or Thaddaeus. 

Tan

name

  • A Chinese surname from Hokkien. 

  • A surname from Vietnamese. 

  • A Chinese surname from Mandarin. 

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