shilly-shally vs stall for time

shilly-shally

verb

  • To procrastinate. 

  • To vacillate. 

adj

  • Indecisive; wavering. 

noun

  • Indecision; irresolution. 

stall for time

verb

  • To intentionally cause a delay; to stop; to wait. 

How often have the words shilly-shally and stall for time occurred in a corpus of books? (source: Google Ngram Viewer )