Third, as the Central Bank of China serves as an agent to safeguard foreign reserves, it does not simply store the money away in a safe, it deposits it in foreign banks in order to earn interest.
貨幣的發行額是中央銀行的負債，其發行基礎之一是作為資產的外匯存底。資產、負債的關係是一對一的，而且是平衡的。如果不用等值的新台幣來換回外匯，而直接由中央銀行撥出外匯來用，外匯撥出之後，又必須換成新台幣才能使用。