China is planning to implement the largest CO₂ emissions trading system in the world. To reduce emissions, the system will be a tradable performance standard (TPS), an emissions pricing mechanism that differs significantly from the emissions pricing instruments used in other countries, such as...

We take for granted today that the assessments, measurements, and forecasts of economists are crucial to the decision-making of governments and businesses alike. But less than a century ago that wasn’t the case—economists simply didn’t have the necessary information or statistical tools to...