The yuan is near its weakest in five years. In January, when it was last this low, investors panicked, thinking China might engineer a big devaluation to boost its economy. The mood this time has been far calmer. That partly stems from the extensive capital controls in place, which make it harder to bet against the yuan. It also reflects the growing credibility of China’s new exchange-rate system: it targets a currency basket, not just the dollar, leading to more gradual depreciation. But the biggest swing factor is the Federal Reserve. Anticipation that America was approaching an interest-rate increase had buoyed the dollar, putting downward pressure on the yuan last month. A weak jobs report on Friday cast doubt on how quickly it will move. As the dollar softens, pressure comes off the yuan and fears of a Chinese devaluation recede still further—a global upside to America’s downside.