a few clowns short of a circus vs few sandwiches short of a picnic

a few clowns short of a circus

few sandwiches short of a picnic

phrase
  • Exhibiting disquiet or unsoundness of mind; not sane; mad. 

How often have the words a few clowns short of a circus and few sandwiches short of a picnic occurred in a corpus of books? (source: Google Ngram Viewer )