来源：https://usafacts.org/articles/who-are-the-uss-top-trade-partners/
来源：https://www.nytimes.com/interactive/2024/01/09/opinion/immigration-in-one-chart.html?unlocked_article_code=1.RE4.THfw.OHySVfN60naI&smid=re-nytopinion
