cooperation vs obstruction

cooperation

noun
  • The act of cooperating. 

  • Association for mutual benefit, such as for purposes of production or purchase. 

  • Active help from a person, organization, etc., such as an orderly sharing of space or resources. 

obstruction

noun
  • The act of obstructing, or state of being obstructed. 

  • Something which obstructs or impedes, either intentionally or unintentionally 

  • The condition of having the natural powers obstructed in their usual course; the arrest of the vital functions; death. 

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