title: Adding a running total column in SQL Server
body: <p>I have a result set from a SQL Server query as below:</p>
  
  <p><strong>Item Week Amount</strong></p>
  
  <pre><code>1     1      500
  1     2     -100
  1     3     -200
  2     1      800
  2     2     -600
  2     3     -800
  </code></pre>
  
  <p>What I want to know is, is it possible to derive a fourth column that gives a running total of amount for each item?</p>
  
  <p>My desired result is as follows:</p>
  
  <p><strong>Item Week Amount Total</strong></p>
  
  <pre><code>1     1      500  500
  1     2     -100  400
  1     3     -200  200
  2     1      800  800
  2     2     -600  200 
  2     3     -800 -600
  </code></pre>
  
  <p>I am using SQL Server 2008</p>