title: changing array in excel based on another cell
body: <p>Is there anyway to update an array size in excel without altering the formula everytime? For example if I have the formula</p>
  
  <pre><code>=sum(A1:A20)
  </code></pre>
  
  <p>and want to update it to</p>
  
  <pre><code>=sum(A5:A20)
  </code></pre>
  
  <p>can I do this without manually dragging and typing for example something that would have the same effect as </p>
  
  <pre><code>=sum(A(C1):A20)
  </code></pre>
  
  <p>where the value of C1 =5</p>