The above is a visualization of the largest down feather exporters of 2015. As you can see, the vast majority of the world's exported down comes from China and Asia. European countries also produce a significant amount of the world's exported down.

For a more detailed view of individual country's import and export data see this down trade graph.

The data comes from UN Comtrade. I used data from 2015, because data from China for 2016 is not available, and China is the largest down exporter. This data represents "Feathers of a kind used for stuffing; down."