Abstract The aim of this paper is to examine the ‘dark matter’ assets in the external sector of the United States in the period 1999:Q1-2018:Q3. The paper investigates data on the balance of payments and international investment position for the US and a group of 18 economies. The research reveals that the US is a privileged economy with respect to foreign income on international investments. The rates of return on its foreign assets are relatively higher, and the costs incurred on its foreign liabilities relatively lower, as compared with the benchmark group. This special privilege of the US relates to equity investments, especially foreign direct investments. Based on prevailing income differentials substantial ‘dark matter’ assets of the US are estimated. Recognising such ‘dark matter’ leads to the conclusion that the US is a foreign creditor, not debtor. The findings shed light on the puzzle as to why the US has a continuing ability to sustain its external position despite mounting foreign liabilities.

中文翻译：

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美国对外贸易中的“暗物质”

摘要本文旨在研究1999：Q1-2018：Q3期间美国外部部门的“暗物质”资产。本文调查了美国和18个经济体的国际收支和国际投资头寸数据。研究表明，就国际投资的外国收入而言，美国是一个特权经济体。与基准组相比，其国外资产的回报率相对较高，而其国外负债的成本则相对较低。美国的这一特殊特权涉及股权投资，尤其是外国直接投资。根据现行的收入差异，估计美国的大量“暗物质”资产。认识到这种“黑暗问题”得出的结论是，美国是外国债权人，不是债务人。这一发现使人们感到困惑，即尽管外国债务不断增加，为什么美国仍然有能力维持其外部地位。