Covered interest parity forces the forward curve to price currency risk as a smooth path of decay. Emerging-market currencies do not decay that way.
Covered interest parity is the condition that links spot and forward exchange rates to the interest differential between two currencies. Under it, the cost of hedging a position in a higher-yielding currency is, to a first approximation, the whole of the yield differential. A dollar investor who buys a 12 percent local bill and hedges the currency through the forward market gives most of the 12 percent back in forward points. After 2008 the relationship stopped holding exactly, as dealer balance-sheet constraints and funding frictions opened persistent deviations, documented in the academic literature on the post-crisis CIP basis. But for the emerging-market investor the problem is not that parity deviates; it is that the forward curve, parity or not, prices currency risk as a continuous path.
Emerging-market currencies do not move continuously. They hold their range for long stretches and then adjust in short, violent steps. In Tranchco’s analysis of State Bank of Pakistan daily data from 2000 to 2025, 97.7 percent of the rupee’s depreciation occurred inside 30-day windows, and 90 percent of volatility episodes returned to calm within nine days. The currency spent most of its life in a regime the forward curve priced as though it did not exist. A continuous hedge therefore overpays, day after day, for a crisis that arrives rarely and briefly, and it tends to become unavailable at any price when the crisis does arrive.
That is why conventional hedging consumes the carry. The premium over the dollar bill is persistent and visible; the hedge that would make it holdable for a pension fund or an insurer costs roughly what the premium is worth, and the unhedged alternative is unavailable to those institutions by mandate. The yield accrues only to capital that faces no hedging constraint, which is mostly local.
The structural answer is to separate the yield from the currency tail rather than to hedge the tail continuously. If the institution best placed to judge the rupee, a domestic balance sheet, elects to hold a bounded share of currency loss for a premium, and a rules-based engine parks exposure at pre-committed thresholds, the dollar holder can hold the yield without buying continuous protection against a discontinuous risk. The senior claim is not free of currency risk; its tail is bounded by the junior layer, and losses beyond that layer remain with the senior. What changes is the price of protection, because protection is now priced by someone who can read the regime rather than by a curve that cannot.
The structure is described on How it works. The evidence is in The Calm Regime, available on request.