hit piece vs slam piece

hit piece

noun
  • A published article or post aiming to sway public opinion by presenting false or biased information in a way that appears objective and truthful. 

slam piece

noun
  • A journalistic or other treatment which portrays its subject in a highly unfavorable manner. 

  • A sexual partner to whom one has no particular emotional attachment. 

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