Here is something I experienced:
I was digging (?) for Ash in a Tier 2 province. The likelihood was listed as "Certain" and the amount 2-4.
I'm really not sure exactly what the multiplier does, so I decided to play with it.
First, I chose x8 (+75%), and got 4. Not sure what kind of effect the x8 had.
Next, I chose x1 (+0%), and got 0. Okay, this seems pretty clear: rather than adding +0%, I was given a 0% chance because I didn't want to take longer digging. This doesn't make any sense, as the probability listed for the area was "Certain", and the amount available was about 950.
Anyone have any ideas on this?