title: Add total SUM from VLOOKUP?
body: <p>I've got 3 columns as follows:</p>
  
  <pre><code>Boolean          Value          Date
  Yes               £3000         01-Jan-2012
  No                £3000         01-Jan-2012
  No                £3000         01-Nov-2012
  </code></pre>
  
  <p>Basically I just need to look at that table and come up with the total value for where Boolean is set to No, however only take those where the month is equal or less than the current month set by the computer time</p>