项目需要，需要更新Peter K. Schott个人网站美国海关数据（https://sompks4.github.io/sub_data.html）
国内IP受限，难以下载dropbox资源，请有能力或有资源的坛友帮忙，感谢感谢，下载好了使用百度网盘传送

2. US HS-level imports and exports (1989-2023)

• Files: imports and exports
• Layout: imports; exports
• Reference: Schott (2008)
• Note: These data were purchased from the US Census Bureau and converted into Stata format; funding from Yale Social Sciences Library is acknowledged gratefully
  

4. US HS-SIC/NAICS concordances

• Files: zip archive (v2024.8.1)
• Reference: Pierce and Schott (JESM 2012)