Bumblefuck vs Timbuktu

Bumblefuck

name
  • An isolated or backward location; the middle of nowhere. 

Timbuktu

name
  • Any proverbially distant or remote place. 

  • A city in central Mali. 

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