Noob question: less zombies

[Professorg]

I would like to know how to spawn less zombies, when I walk into a small town I will often have 10-20 zombies when I would only like 3-5 being as my server is small and the item spawn rate is small.

Variables.sqf [edited by following many broken? tutorials.]
http://pastebin.com/ACidUfjz

Init.sqf
http://pastebin.com/TspJ3MDJ