29% of the top sellers in the top four core Amazon markets - U.S., U.K., Germany, and Japan - are based in China. Down from 35% in January. The percent is the average of the four marketplaces, according to Marketplace Pulse analysis of nearly 90% of the top sellers whose business addresses can be reliably determined.

One of the most significant causes of the downward trend was the disruption to Fulfillment by Amazon (FBA) service. Among the top sellers in the Amazon marketplace in the U.S., 95% of China-based sellers use FBA, compared to 65% for other sellers. Domestic sellers transitioned to fulfill their orders from owned warehouses because Amazon prioritized essential items, baring sellers from shipping new inventory to FBA. International sellers couldn’t make the same change as fast.