apathy vs sluggishness

apathy

noun
  • Lack of emotion or motivation; lack of interest or enthusiasm towards something; disinterest (in something). 

sluggishness

noun
  • The property of being sluggish, unable or unwilling to act quickly. 

  • The state of economic decline, inactivity, slow or subnormal growth. 

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