User rating calculated via reputation points/post count

[steve71]

$post[reputation]/$post[posts]
<?php $userrating = $post[reputation]/$post[posts]; echo $userrating; ?>

eg this puts: 220/93 in the postbit, below the reputation points total -
I just can't get it to calculate and place the quotient instead.

Suggestions?

Do I have to run the php function from reputation.php and then call up the variable from the postbit template?

I see there may be other issues:

http://www.vbulletin.com/forum/showthread.php?t=234222

so I guess I need a plugin. How would I know where the hook location is for this modification?

reputation.php?