obsolescence vs obsoleteness

obsolescence

noun
  • The state of being obsolete—no longer in use; gone into disuse; disused or neglected. 

  • The process of becoming obsolete, outmoded or out of date. 

obsoleteness

noun
  • The quality or state of being obsolete or no longer in use. 

  • The quality of being imperfectly or indistinctly developed. 

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