correlate vs spitting image

correlate

verb

  • To compare things and bring them into a relation having corresponding characteristics. 

  • To be related by a correlation; to be correlated. 

noun

  • Either of a pair of things related by a correlation; a correlative. 

spitting image

noun

  • The exact likeness (of someone). 

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