perceptiveness vs readableness

perceptiveness

noun
  • The state of being perceptive; acumen, discernment, insight 

readableness

noun
  • The property of being capable of being read, legibility. 

  • The property of being easy or engaging to read. 

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