https://www.marketwatch.com/story/ch...ort-2019-01-22Some experts said the Communist Party is concerned that an economic slowdown could spark civil unrest, and want to avoid another Tiananmen Square incident such as seen in 1989. China's growth problems have been compounded by trade tensions with the U.S. A black swan refers to an unforeseen event that could cause turmoil, while grey rhinos refer to a highly likely threat that's currently being ignored.