I'm trying to implement some periodic events (something that would occur every 10 turns for example).

What I tried so far did not work:

<Calculate InternalName="Calc" ValueOwner="World">
<Expression><![CDATA[[TurnNumber] % 2]]></Expression>
</Calculate>
<Calculate InternalName="PostTriggerChance">
<Expression><![CDATA[[Calc] * 999999999]]></Expression>
</Calculate>
<Calculate InternalName="PostTriggerChance">
<Expression><![CDATA[[Calc] * 999999999]]></Expression>
</Calculate>

The thought was to use the modulus to control whether or not the event is triggered, but it doesn't appear to be working. Is it just that that is the wrong syntax for modulus (I used standard C type syntax)?