Filter rule profits found in foreign exchange markets in the early days of the current managed float persist in later periods, as shown by statistical tests developed and implemented here. The test is consistent with, but independent of, a wide variety of asset pricing models. The profits found cannot be explained by risk if risk premia are constant over time. Inclusion of the home-foreign interest rate differential in computing profits has little effect on the comparison of filter returns to those of buy-and-hold.

Filter rule profits found in foreign exchange markets in the early days of the current managed float persist in later periods, as shown by statistical tests developed and implemented here. The test is consistent with, but independent of, a wide variety of asset pricing models. The profits found cannot be explained by risk if risk premia are constant over time. Inclusion of the home‐foreign interest rate differential in computing profits has little effect on the comparison of filter returns to those of buy‐and‐hold.

This paper addresses the issue of whether firms are required to pay an ex ante premium to investors for bearing the risk of interest‐rate changes. A two‐factor APT model with the market and changes in the yield on long‐term government bonds as factors is employed. The paper shows that, empirically, most of the interest‐sensitive stocks are in the utility industries, and that there is reasonable evidence that the interest factor is priced in the sense of the APT. Several sources for the interest sensitivity are considered, and regulatory lags are focused on as a likely candidate.

This paper addresses the issue of whether firms are required to pay an ex ante premium to investors for bearing the risk of interest-rate changes. A two-factor APT model with the market and changes in the yield on long-term government bonds as factors is employed. The paper shows that, empirically, most of the interest-sensitive stocks are in the utility industries, and that there is reasonable evidence that the interest factor is priced in the sense of the APT. Several sources for the interest sensitivity are considered, and regulatory lags are focused on as a likely candidate.