Portfolio and Security Analysis Commons^™

How Much Is Purchasing Power Parity Worth?, Stefan C. Norrbin, C. Mitchell Conover

Finance Faculty Publications

Updating Bilson 's (1984) investment strategy using an out-of-sample forecast procedure, we find much smaller profits from a trading strategy based on purchasing power parity. Though the total profit is significant at a 5 percent level, it is substantially lower than what Bilson found. Our results suggest Bilson's excess profits are due to the sample of data used and the in-sample nature of the tests. Hence, this paper demonstrates that the simple investment strategy leads to the same conclusion that econometric testing does; namely, that purchasing power parity is only marginally useful in forecasting exchange rates.