The study looked at how exporting companies in China affect productivity growth. They found that many exporting firms struggle to survive, leading to a lot of turnover. The changes in these firms contribute to almost half of the productivity improvements. Most of the improvement comes from differences between firms, rather than firms entering or leaving the market. This suggests that there are issues with how resources are distributed in the market, possibly due to uneven development in different regions, monopolies in certain industries, or state-owned companies.