Number of systems on ships

I have a rather odd question.  What are the average number of systems
people put on a ship?  For instance a Mass 18 FTL escort could have 9
c-bats but what is the average number of systems?  I'm curious as to
what
sizes I would need to make a ship diagram for the "average" ship.

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   +		 Eric Fialkowski	       +
  +    http://netnow.micron.net/~ericski      +
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