marketplace vs shopping center

marketplace

noun
  • An open area in a town housing a public market. 

  • A place or sphere for the exchange of anything, such as ideas or fashions. 

  • The world of commerce and trade. 

  • The space, actual or metaphorical, in which a market operates. 

shopping center

noun
  • An area, either enclosed or unenclosed, hosting multiple retail establishments; a shopping mall. 

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