China's Defense of the Yuan Is Growing More Costly: Chart

China is burning through cash as it battles to support the yuan.

The nation’s foreign currency reserves tumbled by a record $108 billion in December as the central bank sold dollars to stem a slide in the currency. That was about four times greater than analysts predicted in a Bloomberg survey, and reduced the stockpile to the lowest level in three years. Despite the intervention, the yuan’s descent has steepened, with the currency falling to a five-year low on Thursday.