cooker hood vs extractor fan

cooker hood

noun
  • An electrical kitchen device fitted over a cooker and connected to a flue designed to suck off any vapours from cooking. 

extractor fan

noun
  • A type of fan designed to remove moisture from a room, or dust or fumes from certain environments. 

How often have the words cooker hood and extractor fan occurred in a corpus of books? (source: Google Ngram Viewer )