title: identify duplicates in a column then find the maximum value of adjacent column values in excel
body: <p>This is a constantly growing file of part names. Each time a part is revised a new test part needs to be made of the revision so we want to keep track of the highest level</p>
  
  <p>Based on duplicates in column A, I am trying to show the current highest rev level (alphanumeric) from column B in column C. </p>
  
  <p>Using the code command I can get a value for the Rev Level up to Z, But I need to account for revision levels beyond Z (AA or AB etc)</p>
  
  <p><img src="https://i.stack.imgur.com/omo09.jpg" alt="sample spreadsheet"></p>
  
  <pre><code>PN         rev Max Code
  1-QR-728    -   C   45
  4-QR-63     D   D   68
  2-QR-312    C   D   67
  1-QR-728    A   C   65
  28-QR-240   A   K   65
  2-QR-312    D   D   68
  6-QR-257    AA  AB  65
  1-QR-728    B   C   66
  28-QR-240   K   K   75
  4-QR-198    -   -   45
  1-QR-728    C   C   67
  5-QR-223    D   D   68
  6-QR-257    AB  AB  65
  </code></pre>