ZOMG vs shiver my timbers

ZOMG

intj
  • An emphatic form of oh my God. 

shiver my timbers

intj
  • A mild oath expressing surprise, disbelief or annoyance. It is stereotypically regarded as being uttered by pirates. 

How often have the words ZOMG and shiver my timbers occurred in a corpus of books? (source: Google Ngram Viewer )