big box vs warehouse club

big box

noun
  • A large self-service store, usually on a single level, with few interior walls, owned and run by a corporation 

warehouse club

noun
  • A large retail store holding a wide selection of goods for sale at discounted prices to members of the club. 

  • The club itself. 

How often have the words big box and warehouse club occurred in a corpus of books? (source: Google Ngram Viewer )