hara-kiri vs taking one's own life

hara-kiri

noun
  • Ceremonial suicide by disembowelment, as by slicing open the abdomen with a dagger or knife: formerly practised in Japan by the Samurai when disgraced or sentenced to death. 

  • Suicide or any suicidal action. 

  • An act against one's own interests. 

taking one's own life

How often have the words hara-kiri and taking one's own life occurred in a corpus of books? (source: Google Ngram Viewer )