shipping vs tonnage

shipping

noun
  • The body of ships belonging to one nation, port or industry; ships collectively. 

  • The transportation of goods. 

  • Passage or transport on a ship. 

  • Navigation. 

  • The cost of sending an item or package via postal services. 

tonnage

noun
  • The total shipping of a fleet or nation. 

  • The number of tons of water that a floating ship displaces. 

  • The capacity of a ship's hold etc in units of 100 cubic feet. 

  • A charge made on each ton of cargo when landed etc. 

  • The number of tons of bombs dropped in a particular region over a particular period of time. 

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