Farming Combat Sites

Maybe someone can help me with this.

My question is relating to combat sites in null-sec. and the Activity Defence Multiplier.

If I am ratting in a certain system using combat sites, is the theory correct as the ADM rises then more combat sites will appear in that system and especially ones that are more lucrative such as Sanctums or Havens?

Basically farming combat sites, not sure of the mechanics of it but I think you know what I am trying to achieve. Thanks

Definitely a reason why ADM is more prevalent in null then any other upgrade, with the changes coming, more lucrative.