self-abnegation vs unselfishness

self-abnegation

noun
  • An act of self-denial. 

  • The denial or invalidation of one's own needs, interests, etc. for the sake of another's; the setting aside of self-interest. 

unselfishness

noun
  • The state of being unselfish. 

How often have the words self-abnegation and unselfishness occurred in a corpus of books? (source: Google Ngram Viewer )