I don't think you really need rounding. It is rarely needed and can be dangerous. This is a typical situation.
Much more likely that you need a rounded string presentation of a number to show in UI, and this is completely different thing, which is really needed very often.
So, you need to use
string.Format<code> with appropriate format string.<br />
See:<br />
<a href="http://msdn.microsoft.com/en-us/library/system.string.format.aspx">http:
<a href="http://msdn.microsoft.com/en-us/library/dwhawy9k.aspx">http:
<a href="http://msdn.microsoft.com/en-us/library/0c899ak8.aspx">http:
<br />
<dd>—SA</dd>