ballot box vs voting booth

ballot box

noun
  • A sealed box with a slit, into which a voter puts a completed voting slip. 

  • The process or method of voting. 

voting booth

noun
  • A small enclosed compartment where a voter may register a vote in private; it may house some voting machine, or just have a pencil for marking a voting slip. 

How often have the words ballot box and voting booth occurred in a corpus of books? (source: Google Ngram Viewer )