Four months into office, Argentine President Javier Milei has pulled off a critical feat in a country long ravaged by runaway inflation: He stabilized the currency.

The peso has, in fact, not only stopped plunging day after day but in one key foreign-exchange market — there are many of them here, a byproduct of the country’s web of byzantine rules — it’s actually rallying sharply. The peso has soared 25% against the dollar over the past three months in the market, known as the blue-chip swap, that is used by many investors and companies. That’s more than the gains posted by any of the 148 currencies that Bloomberg tracks against the dollar.