grounds vs paper trail

grounds

noun
  • Basis or justification for something. 

  • The sediment at the bottom of a liquid, or from which a liquid has been filtered. 

  • The collective land areas that compose a larger area. 

paper trail

noun
  • A written record, history, or collection of evidence. 

  • Records left by a person or organization in the course of activities. 

  • Physical evidence of something that occurred in the past. 

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