Using movement data from the map-and-search firm, Baidu, Morgan Stanley assesses that under 40% of the individuals who left top-level Chinese urban communities for the holiday have returned to work. Around this time a year ago, almost all had. Checking the state of China’s economy is precarious under the most favorable circumstances. Now, the undertaking is troublesome and necessary because of the coronavirus outbreak. With most official information for January February still weeks away, institutional investors are poring over everything from nitrogen-dioxide emissions to movie-ticket sales and traffic congestion. Some imaginative thoughts for checking the economy are more helpful than others. Fixating on power utilization and film ticket sales is less useful than direct information on individuals’ movement back to work—or scarcity. Much of these measurements recount to a related story: Things are bad.