以中國對美國資本回流率檢視貨幣權力理論

Testing the Monetary Power Theory: A Case of China's Capital Account/Current Account to the U.S.

Benjamin J. Cohen 和 Eric. Helleiner 對貨幣權力進行概念論述，但欠缺具體操作指標，學者趙文志依 Cohen 貨幣權力理論中的延遲權力與轉移權力， 提出延遲權力中有中、美兩國外匯儲備量、國債發行規模的借貸能力，轉移權力以貿易占 GDP 比值的開放程度，共三項具體指標，指出美國開放度比中國低、但美元流動性與借貸能力高於中國，說明美國對中國有貨幣權力， 但該文無法說明中國外匯存底和貿易開放程度都高於美國，但為何是美國擁有貨幣權力，顯然中美貨幣權力關係更多的決定於借貸能力，而非另外二者。本文觀察中國對美國資本帳占經常帳比例形成的對美國資本回流率，作為檢視借貸能力的具體指標，同時定義美國貨幣權力表現在美國有能力影響人民幣匯率持續走升。發現中國對美國資本回流率和人民幣匯率呈相當正關聯，將中國對美國資本回流率和人民幣匯率做為補充貨幣權力的具體可觀察指標。觀察中國從 2008 至 2013 年改變購買美國債券資產行為，出現若干增減循環波段，同時增持日本債券資產和進行對外直接投資，造成中國美國資本帳變化較大，改變近 20 年來中國對美國資本帳幾近甚或超越經常帳的常態，資本帳占經常帳比例巨幅降至 30%左右，相對應的人民幣匯率也隨此出現不同速度的升值速率。中國對美國資本回流率和人民幣匯率走勢大致相符，但若干年度出現時間差。分析原因有二，除中國持有美國債券為長天期造成出售時間差外，發現中國處理美國國債和美國國債以外債券資產有所不同，前者更能反映與人民幣匯率走勢關聯。即在 2008 年後扣除中國持有美國國債以外債券資產後，單以美國國債和以此為計算基礎的中國對美國資本回流率與同時期人民幣匯率呈高度正相關，說明在美、中兩國案例中貨幣權力確有解釋力，而貨幣權力中的借貸能力更有關鍵作用。

Although Benjamin J. Cohen and Eric Helleiner have developed narratives on Monetary Power, there is no lear operational definition of the term. Based on Cohen's discussion of the power of delay and the power of transfer, Chou Wen-Chi came up with three criteria to measure Monetary Power: foreign reserve, outstanding national debt, and percentage of trade in GDP. Using these criteria, he pointed out that although the US is less trade- dependent, liquidity of US Dollar and borrowing ability of the US are both higher. Thus, the US holds Monetary Power over China. This paper observed a cyclical buying behavior of China on US Government Bonds from 2008 to 2013. During the time, China increased its holding of Japanese Bonds and foreign direct investment. China's Capital Account/Current Account rate to the U.S. is positively correlated with the exchange rate of RMB – thus, an indicator of Monetary Power. Though China's Capital Account/Current Account rate to the U.S. matched the exchange rate of RMB, there were time lags and inconsistency in several fiscal years. First reason was that most U.S. liability assets held by China were in the form of long-term ecurity. Second, China differentially processes its holding of U.S. treasury and U.S. agency, bonds, and equity. China's holding of U.S. treasury more strongly matches the RMB exchange rate. In the case of China's Capital Account/Current Account rate, the Monetary Power theory possesses effective explanation ability, particularly its theory on borrowing capacity.