assessment vs rating

assessment

noun
  • An appraisal or evaluation. 

  • The act of assessing or an amount (of tax, levy or duty etc) assessed. 

rating

noun
  • An evaluation of status, especially of financial status. 

  • An enlisted seaman not a commissioned officer or warrant officer. 

  • A number, letter, or other mark that refers to the ability of something. 

  • A position on a scale. 

  • A quantitative measure of the audience of a television program. 

  • A seaman in a warship. 

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