Pippi Longstocking vs redpoll

Pippi Longstocking

noun
  • A person, especially a girl or woman, with long or flamboyant red hair, especially in pigtails or parted down the middle, and prominent freckles. 

  • A person, especially a girl or woman, given to headstrong, wild behaviour, flights of fancy, or irrepressible optimism. 

redpoll

noun
  • Any of various finches in the genus Acanthis (syn. Carduelis), which have characteristic red markings on their heads. 

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