title: Add %age discount to Opencart product
body: <p>I am new to opencart. I have a task at hand. I need to add few discounts to some products. There are two types of discounts that i have to add.</p>
  
  <ol>
  <li>Fixed price. Like if something is of $10, i offer that at $8.</li>
  <li>%age discount. Like I want to offer 50% off on the product.</li>
  </ol>
  
  <p>What i found is that open cart has a discount tab in it's backend but it has options for only fixed price discount.</p>
  
  <p>I have attached its snapshot for reference.</p>
  
  <p><img src="https://i.stack.imgur.com/HGDNN.png" alt="enter image description here"></p>
  
  <p>How can I add a percentage discount option?</p>