interested vs matter-of-fact

interested

adj
  • Having an interest (stake); being a stakeholder; motivated by considerations of self-interest; self-serving. 

  • Owning a share of a company; being a shareholder. 

  • Having or showing interest (attention or curiosity). 

matter-of-fact

adj
  • lacking emotion or colour 

  • of, or relating to facts only; literal, realistic 

  • straightforward, blunt, frank; treating the situation as normal; not embarrassed, coy, or dramatic. 

How often have the words interested and matter-of-fact occurred in a corpus of books? (source: Google Ngram Viewer )