1. dollar exchange rates from 1946-50 were used to derive a free U.S. dollar-pound sterling exchange rate (Figure 22). Per the Bretton Woods agreement, the U.S. dollar during served as the world's primary reserve currency, and the exchange rates of other currencies, including pound sterling, were officially fixed against the U.S. dollar. As has been described in earlier chapters, a chronic U.S. dollar shortage afflicted Britain and other countries during this time. For these and other reasons it is useful to test for breakdates in sterling;New daily exchange rate data obtained from the Swiss National Bank Archive for the Swiss franc-free pound sterling and Swiss franc-U.S
2. A monetary model of the parallel market for foreign exchange;P R Ag�nor;Journal of Economic studies,1991