title: Spreadsheet lookup by empty cell as a key
body: <p>I know how to lookup last non-empty value in a row using 
  <code>=LOOKUP("X";$B2:$E2;$B1:$E1)</code></p>
  
  <p>But if I try to use an empty cell as a key, it causes an #N\A as a result.</p>
  
  <p>How can I get "<strong>5 Jan</strong>" as a result in this example? I need to get date that matches up last empty cell in a row.
  <a href="https://i.stack.imgur.com/Xtvy4.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Xtvy4.png" alt="enter image description here"></a></p>