TOKYO— Japan’s manufacturing activity grew for an 11th straight month in December, but at a slower pace than in the prior month as output and new order growth softened while cost pressures stayed elevated. Businesses benefited from the weakening impact of the coronavirus pandemic as they shook off some of the drag of the health crisis, though new export sales growth eased amid a rise in COVID-19 cases in South Korea. The final au Jibun Bank Japan Manufacturing Purchasing Managers’ Index (PMI) in December fell to 54.3 on a seasonally adjusted basis, easing from the previous month’s 54.5. The figure, which compared with a 54.2 flash reading, still pointed to a solid improvement in operating conditions in the manufacturing sector. “Domestic markets were buoyed by a gradual recovery from the COVID-19 pandemic,” said Usamah Bhatti, economist IHS Markit, which compiles the survey. A recovery in parts supplies eased some of …