Many policy assessments, such as the effect of a currency revaluation on trade balances, are sensitive to the share of domestic content in a country’s exports. The current method might be problematic for countries with a high share of processing exports, such as China, Mexico and Vietnam. This column introduces a new method for calculating domestic content shares and presents some striking estimates for China. The share of domestic content in China’s exports is about 50%, much lower than most other countries: this implies that an exchange rate appreciation is likely to have a smaller effect on China’s trade surplus than for other countries.