disinterest vs dispassionateness

disinterest

noun
  • The absence of interest (bias or stake). 

  • An absence of interest (attention or curiosity). 

verb
  • To render disinterested. 

dispassionateness

noun
  • The state or quality of being dispassionate. 

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