title: converting date in to second in excel
body: <p>In attached link there is an image of excel file. I would like to convert date and time in to seconds. I am using below mentioned formula for that. </p>
  
  <p>for sec: </p>
  
  <pre><code> =(STUNDE(A243) * 3600 + MINUTE(A243) * 60 + SEKUNDE(A243))
       -(STUNDE($A$11) * 3600 + MINUTE($A$11) * 60 + SEKUNDE($A$11))
  </code></pre>
  
  <p>for hr:</p>
  
  <pre><code> =B243/3600
  </code></pre>
  
  <p>but If you see in sheet, my values become minus when the date is changed from 13 to 14. How I can make it in positive?</p>
  
  <p><img src="https://i.stack.imgur.com/CyOta.png" alt="enter Data sheet"></p>