Twin Deficits and Currency Crises: Warning Signs to Watch

[Fairman]

Twin Deficits and Currency Crises: Warning Signs to Watch

Some currency collapses look sudden but follow recognizable patterns. Understanding the warning signs helps you avoid being surprised.

Economists point to a set of vulnerabilities. A large current account deficit means the country relies on foreign capital. A large government budget deficit adds to borrowing needs. Together they are called the twin deficits. When foreign investors become unwilling to finance them, the currency falls.

Other warning signs include low foreign exchange reserves relative to short-term foreign debt, a high share of debt denominated in foreign currencies, a fixed or managed exchange rate that appears overvalued, rapid credit growth, and political instability.

Triggers vary. A rise in US interest rates can draw capital out of emerging markets. A global risk-off episode can freeze financing. Loss of confidence in the central bank or government, or a rating downgrade, can start a run.

Historic examples include the Asian financial crisis of 1997, the Russian default of 1998, and the Turkish and Argentine episodes in later decades. In each, an apparently stable peg or managed rate gave way, and the move was much larger than gradual trends suggested.

For traders, the lesson is to be cautious about carry trades in vulnerable currencies. High yields are compensation for risk.

Check reserve levels, external debt, and the current account regularly.

Practical step: list the current account balance, reserves, and external debt for one emerging economy whose currency you follow.

[Fairman]

Reserves versus short term foreign debt is the ratio I'd look at first. If a country can't cover a year of maturing foreign debt from reserves, it's dependent on investors staying friendly. Economists call this the Greenspan Guidotti rule, and it's a useful quick screen. The IMF and the country's central bank usually publish the numbers, though not always quickly. For retail traders who touch emerging market currencies, a falling reserve number combined with a big current account gap is a reason for caution. Even if nothing happens for months, the downside when sentiment turns can be several times larger than the normal daily range.

[Fairman]

The scary part of these episodes is how quiet they can look beforehand. A managed rate that hasn't moved for months is not the same as a safe rate. In fact the flat chart can make people take bigger positions because the volatility looks low. Then the peg or band gets adjusted and the currency jumps several percent overnight, with no chance for stops to work. If a currency is held steady by the central bank while reserves are falling, I'd assume the risk is building rather than shrinking. That's a pair to watch from the sidelines or trade very small, not one to load up on because it looks calm.

[LondonNewsTrader]

The UK is an interesting case of this outside emerging markets. Sterling has run a sizeable current account deficit for years, and the September 2022 mini-budget showed what happens when the fiscal side suddenly looks worse: cable fell to a record low near 1.035 within days and gilt yields spiked until the Bank of England stepped in. No peg broke, but the mechanism was the one you describe, foreign investors demanding more to keep financing.

For anyone trading GBP around data, that's a reason to watch the quarterly current account release and the public finances numbers more closely than most traders do. They rarely move price on the day, but they shape how hard the market reacts when confidence wobbles.