inadequateness vs underage

inadequateness

noun
  • inadequacy 

underage

noun
  • A deficit or shortfall in funds, inventory, or capacity. 

adj
  • Not yet a legal adult; still a minor. 

  • Below the legal age for some activity, such as drinking or having sex. 

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