The "Ring of Fire" - that is the portion of the Pacific rim where volcanic activity occurs,
is nearly 100 % subduction, because most volcanos require subduction to form.
On the other hand, the areas where subduction actually is occurring includes the
entire western Pacific north of South Island, New Zealand, the Aleutian Arc down
to SE Alaska, small portions off the west Coast of the U.S, and then all the way
from Mexico through Central America to southern Chile in South America.
The Pacific-Antarctic ridge makes the southern portion of the plate, and this
is a spreading center, not a subduction zone. In all this makes up about 70% of
the circumference of the Pacific.