service area vs service station

service area

noun
  • A place built alongside a limited-access road where one can stop to buy fuel, refreshments, and so on. 

service station

noun
  • a filling station, gas station or petrol station; a facility selling fuel for road motor vehicles 

  • a service area 

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