latrine vs portapotty

latrine

noun
  • Any facility or device used for urination or defecation, whether toilet, lavatory, or outhouse. 

  • An open trench or pit used for urination and defecation. 

portapotty

noun
  • A portable restroom. 

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