美国净对外负债前景与美元汇率调整

The Outlook of the Net Liabilities of the U.S. and the U.S. Dollar Exchange Rate Adjustment

本文首先对美国的商品贸易账户、收入账户和国际投资头寸估值效应的主要决定因素进行考察,进而对建立的模型进行了历史检验,并在此基础上对美国净对外负债的前景进行了预测。结果表明,未来十年,如果美元加权汇率保持稳定或上升,将会给美国对外负债的调整造成压力;如果美元加权汇率贬值10%-20%,那么根据本文的实证结果,美国的净国际投资头寸与当期名义GDP之比将有可能在20%-30%之间达到最高点,并在此之后保持稳态,而且存在进一步改善的可能性。所以在今后相当长时期内,汇率调整有可能是美国对外负债调整的最优方案之一。

In this paper, we study the determinant factors of U.S. goods and services account, income account and international investment account firstly. Then we test the model with history data. After that, we forecast the situation of the U. S. international investment position. The result shows that there will be greater stress on the adjustment of U.S. international investment position if the weighted dollar exchange rate remains firm or rises. For example, if the U.S. dollar devalues 10%- 20%, the ratio of net intemational investment position to GDP will stand at the peak of 20%-30% and then in steady state. Thus the exchange adjustment may be one of the most effective policies in the future. This to say the U.S. might adopt weak dollar policy.