expropriation vs petty theft

expropriation

noun
  • The act of expropriating; the surrender of a claim to private property; the act of depriving of private propriety rights. 

petty theft

noun
  • A theft of property having a value lower than a certain small amount set forth in a statute, and considered to be a less serious class of crime. 

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