plug nickel vs tittle

plug nickel

noun
  • A nearly worthless amount. 

tittle

noun
  • A small, insignificant amount (of something); a modicum or speck. 

  • Any small dot, stroke, or diacritical mark, especially if part of a letter, or if a letter-like abbreviation; in particular, the dots over the Latin letters i and j. 

verb
  • To chatter. 

How often have the words plug nickel and tittle occurred in a corpus of books? (source: Google Ngram Viewer )