I'm pretty sure it was -4cm, but I'm not 100% sure. I'm injured and can't get to them at the moment. If you dm me and remind me I can measure them in a few weeks.
My Rangers are the 188 and more of a freestyle powder ski. My Big Stix's are 192 and mounter further back. I personally think you should mount your Rangers further back than -4 unless your preference is to spin and take off switch more than land cliffs and ski powder.