title: Jasper report : Round variable sum value
body: <p>I have a variable that is the sum of detail values (each value with three decimals).</p>
  
  <pre><code>&lt;variable name="montantTtc2" class="java.math.BigDecimal" calculation="Sum"&gt;
          &lt;variableExpression&gt;&lt;![CDATA[$F{montantTtc}]]&gt;   &lt;/variableExpression&gt;
      &lt;/variable&gt;
  </code></pre>
  
  <p>I want, once the sum is done, to round the result to two decimals. (without rounding each detail value to 2 decimals).<br>
  How can I do that?</p>