In developed economies such as the United States，Europe and Japan，the manufacturing PMI has been below the line of expansion and contraction for several months and hit a new low in many years. Meanwhile，leading indicators such as consumer confidence and investor confidence have also been declining. In the face of continued external shocks and structural slowdown of the domestic economy，China’s economy grew by 6.2% in the first three quarters of 2019，showing a trend of decline quarter by quarter. In the future，the economic growth rate will continue to decline or continue. Based on the “slowdown scenario”，we estimate that China’s economy will grow 6.1 percent in 2019，still within the annual target range of 6-6.5 percent，and 5.8 percent in 2020. According to our estimates，the increase in welfare costs for US consumers alone is as high as $9.558 billion，while China’s welfare losses are also $3.739 billion. While China’s traditional advantages are fading，we must continue to promote high-quality economic development and adapt itself to the “great power model” featuring domestic demand and innovation.