ferocity vs savagery

ferocity

noun
  • The condition of being ferocious. 

savagery

noun
  • Savage or brutal behaviour; barbarity. 

  • Wild growth of plants. 

  • A violent act of cruelty. 

  • Savages collectively; the world of savages. 

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