comp vs ghostwrite

comp

verb
  • To accompany, in music. 

  • To provide (someone) with a complimentary item, such as a ticket. 

  • To compose (a visual design); to make a composite. 

  • To provide a complimentary item, such as a ticket. 

ghostwrite

verb
  • To author a literary work or speech in the place of another. 

  • To write under the name of another (especially literary works). 

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