certificate(s) vs inventory

certificate(s)

inventory

noun
  • The total set of a (specified) linguistic feature (within a language etc.) 

  • The stock of an item on hand at a particular location or business. 

  • A detailed list of all of the items on hand. 

  • The process of producing or updating such a list. 

  • A space containing the items available to a character, especially that in a video game, for immediate use. 

verb
  • To take stock of the resources or items on hand; to produce an inventory. 

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