litotes vs simile

litotes

noun
  • An ironic figure of speech whereby something is stated by denying its opposite, particularly the negation of a negative quality to say something positive. 

simile

noun
  • A figure of speech in which one thing is explicitly compared to another, using e.g. like or as. 

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