||China is the world’s second-largest economy and its output data are being closely watched. The release of the latest GDP data by China’s National Bureau of Statistics can be felt on stock markets around the globe, and may influence a broad range of economic decisions ranging from companies’ investment strategies to monetary policy. But China’s GDP data are poorly understood. GDP in one year may be revised upward by 16.8 percent, while rural household consumption falls by 26.6 percent and government consumption rises by 41.1 percent. Data series appear to be revised every few years, even outside official benchmark revisions. The labor share in income is retrospectively revised to fall by more than 10 percent, and a few years later it is raised back to near its original level. Nominal data are retrospectively revised when an economic census newly discovers previously uncounted economic activities in the census year, but real growth rates are not retrospectively revised, implying a revised deflator for periods many years earlier. Data series end while series with similarly sounding labels newly start. The list is long. But explanations of what is happening to the data are almost always missing. This manuscript first specifies what official data are available for •GDP, including sectoral value-added, with a subsector breakdown for the tertiary sector as well as for industry (in the latter case limited to certain types of enterprises), •aggregate expenditures, including the different types of expenditures, and •national income, including income components. It then proceeds to examine the quality of these data: it explains statistical breaks, resolves inconsistencies to the extent possible, and describes the limitations of different series. Third, it recommends particular output series for use in economic analysis and provides these data.