backpacking vs day trip

backpacking

noun
  • hiking and camping overnight in backcountry with one's gear carried in a backpack. 

  • low-cost, generally urban, travel with minimal luggage and frugal accommodations. 

day trip

noun
  • An excursion that lasts most of the day. 

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