Italy is about 8% currently isnt it?
As you say, we can ignore Chinas 3%.
So if we ignore China's figures. The worldwide confirmed cases is 163,939 (n/a China)
Total deaths at 10,030. Minus China's deaths, that leaves us with 6,785
So that gives us about a 4% mortality rate as things stand.
from here: https://www.worldometers.info/coronavirus/#countries
But the thing is, it could all be for nought cause there aren't enough tests happening.