glum vs groaning

glum

adj
  • despondent; moody; sullen 

groaning

adj
  • That groans. 

  • Heavily laden, as if to creak under the strain. 

noun
  • A low sound associated with extended suffering, sorrow, and toil. 

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