complete shift vs shakedown

complete shift

shakedown

noun
  • Extortion, especially through blackmail 

  • A thorough search; a frisk 

  • A trial or test period, especially of a ship or aircraft 

  • An improvised bed. 

adj
  • that tests the performance of a ship or aircraft 

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