declination vs depravation

declination

noun
  • A refusal. 

  • At a given point, the angle between magnetic north and true north. 

  • At a given point, the angle between the line connecting this point with the geographical center of the earth and the equatorial plane. 

depravation

noun
  • Detraction; depreciation. 

  • The state of being depraved or degenerated; degeneracy; depravity. 

  • Change for the worse; deterioration; morbid perversion. 

  • The act of depraving, or making anything bad; the act of corrupting. 

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