frustrate vs not worth salt

frustrate

adj
  • ineffectual; useless; fruitless. 

verb
  • To cause stress or annoyance. 

  • To disappoint or defeat; to vex by depriving of something expected or desired. 

  • To hinder or thwart. 

not worth salt

adj
  • Worthless. 

How often have the words frustrate and not worth salt occurred in a corpus of books? (source: Google Ngram Viewer )