Foreign exchange rates are determined by various factors.

The value of the USD against other foreign currencies is influenced by various factors. An increase in the US current account surplus (D) would likely strengthen the value of the USD. This is because a current account surplus indicates that the US is exporting more goods and services than it is importing, leading to higher demand for the USD by foreign buyers who need it to pay for US exports. This increased demand for the USD relative to other currencies results in an appreciation of the USD.