guardianship vs sponsorship

guardianship

noun
  • The office or position of one acting as a guardian or conservator, especially in a legal capacity. 

sponsorship

noun
  • The state or practice of being a sponsor. 

  • The aid or support provided by a sponsor; backing or patronage. 

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