Vehicle emissions control programs in China have made considerable progress, mainly attributed to the uptake of emissions control technologies driven by increasingly stringent standards and improved fuel quality. Nevertheless, challenges remain regarding compliance with emissions standards for vehicles under real-world driving conditions. In addition to increasing amount of evidence in Europe, recent tests in China have shown that emissions under real-world driving conditions are in some instances found to be substantially higher than laboratory-certified levels. And when the large amount of data is pooled together, the trend is clearer than ever. By collecting and pooling existing real-world emissions data from multiple sources, the ICCT was able to perform a "meta-study" to show trends of real-world emissions from China 0 to the latest China 5/V vehicles.