accompanying vs coöccurrence

accompanying

noun
  • That which accompanies; accompaniment. 

adj
  • Present together. 

coöccurrence

noun
  • The fact of a thing occurring simultaneously with something else; correlation. 

  • An instance of a thing occurring simultaneously with something else; coïncidence. 

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