alteration vs unpredictability

alteration

noun
  • The act of altering or making different. 

  • The state of being altered; a change made in the form or nature of a thing; a changed condition. 

unpredictability

noun
  • The quality of being unpredictable. 

  • Something which is unpredictable. 

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