title: Check the number of unique cells in a range
body: <p>I have an excel sheet. </p>
  
  <p>Under column E, I have 425 cells with data. I want to check if the same data (i.e. text inside the cell) is repeated anywhere else in any of the remaining 424 cells under column E. How do I do this? </p>
  
  <p>For example, in E54 I have<br>
  <code>Hello Jack</code></p>
  
  <p>How would I check this value to see if it was in any other of these cells?</p>