I did a little research and I found this info for the Mazda 2 (Im assuming its for the post 2007 model, or perhaps the lastest model?):
Mazda 2
6.5” x 15”
PCD 4×100mm
Offset 43mm
So it looks like I was wrong and it is 4x100 after all.

You can understand the confusion though when you read this info I found: "This version is built on the new DE platform, which Ford also used for the 2008 Ford Fiesta. It deploys light weight material and reduces the overall dimensions of the car."
So I just assumed that the latest model was built in the same Ford factory in Spain as the DY model (pre 2007), however, today after some more research, I also found this: "The vehicles were built in Ujina Plant No.1 (U1) in Hiroshima, with additional Mazda2 began at the Ujina Plant No.2 (U2) in June 2007.[19] Additional vehicles were built in Hofu, Japan".
So they are now built in Japan, but with the same platform used for the latest Ford Fiesta...Looks like Mazda bolt their own axles onto the same platform, hence the PCD difference.
.