Early tanker tracking data indicate that China’s oil imports from Saudi Arabia may be about to take a hit. Just under 3.5 million tons of crude left the Middle East country for the Asian nation’s ports in December, a 20 percent month-on-month drop to the lowest in 2017. Deliveries take about 20 days to reach China, which will next publish country-by-country imports data around Jan. 22, showing whether Saudi oil flows were curtailed on the key trade route.