SHANGHAI—More than half of U.S. multinational companies in China have reduced their annual revenue projections, mostly due to the recent COVID-19 outbreak in Shanghai, according to a joint survey by the American Chambers of Commerce in Shanghai and Beijing published on Friday. Responses to the survey, conducted with 167 companies operating throughout China including 76 in manufacturing, found 82 percent of manufacturers reported slowed or reduced production due to a lack of employees, inability to obtain supplies, or lockdowns. More than half, or 54 percent, have cut 2022 revenue projections following the outbreak, though 38 percent said it was too early to estimate the impact. Some manufacturers in Shanghai, particularly in the automotive industry, have resorted to operating with a “closed-loop”, wherein employees remain confined to the premises in order to keep production lines running, while outside suppliers are sealed off. Eric Zheng, president of the American Chamber of Commerce …