flank steak vs sirloin

flank steak

noun
  • A beef steak cut cut from the abdominal muscles or buttocks of the cow. 

sirloin

noun
  • A cut of beef from the middle of the back (corresponding to short loin and partly rib in US English). 

  • A cut of beef from the lower part of the back, where the last ribs are (called rump in UK English). 

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