Strange SpamAssassin Statistical Performance

[Jerome Cartagena]

I have been a member of the mail list for a couple months and have been 
intently watching the active discussions taking place.  This is my 
first time posting so I'd like to greet everyone "hello" and introduce 
myself.

I am using spamassassin through MailScanner on a University mail server 
to help perform spam checks.  I am using:
SpamAssassin version 3.0.2
  running on Perl version
I have setup some scripts (spam-stats) to generate MRTG stats to help 
give us an idea of how well performance is going.  My main 
problem/question is that according to our statistics we are reaching 
some sort of upper bound on spam scanning performance.  I have attached 
2 files to help demonstrate what I am talking about.  I am wondering if 
we are hitting some sort of performance limit on our mail scanning 
machines or is it simply the case that this is how much spam we are 
actively collecting.  I'd appreciate any comments, ideas, or 
suggestions on a possible explanation regarding this situation.

Thank you in advance for all replies,
~Jerome Cartagena

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