improv vs off the cuff

improv

verb
  • To perform improv. 

noun
  • Improvisation. 

  • A form of live entertainment characterized by improvisation and interaction with the audience. 

off the cuff

prep
  • In an off-the-cuff manner. 

How often have the words improv and off the cuff occurred in a corpus of books? (source: Google Ngram Viewer )