on cloud nine vs rhapsodic

on cloud nine

prep
  • In a state of elation; very happy; blissful. 

rhapsodic

adj
  • highly emotional; rapturous 

  • Of or relating to rhapsody; consisting of rhapsody 

  • confused, unconnected 

How often have the words on cloud nine and rhapsodic occurred in a corpus of books? (source: Google Ngram Viewer )