early days vs preadolescence

early days

noun
  • Initial stages of a project. 

  • A time too soon to make a decision or come to a conclusion. 

  • The initial period of an innovation 

preadolescence

noun
  • The period between childhood and adolescence, between the ages of about 9 and 11 for girls, and 10 and 12 for boys. 

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