odometer vs pedometer

odometer

noun
  • An instrument, usually embedded within the speedometer of a vehicle, that measures the distance the vehicle has traveled since production. 

  • A wheel used by surveyors, which registers distance traveled. 

pedometer

noun
  • A device, often electronic, that measures the number of steps taken, and thus estimates the distance walked. 

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