anyone's guess vs unsettled

anyone's guess

noun
  • A mystery; something unpredictable. 

unsettled

adj
  • Unpaid. 

  • Not populated, having no settlers or other inhabitants. 

  • Disturbed, upset. 

  • Not in a steady condition, uncertain, subject to change. 

How often have the words anyone's guess and unsettled occurred in a corpus of books? (source: Google Ngram Viewer )