TOKYO—Japan’s manufacturing activity grew at the fastest pace in nearly eight years in January on stronger output and new orders, while cost pressures stayed elevated as firms continued to face supply chain delays. The supply chain disruptions forced businesses to build up safety stocks, with the survey showing holdings of raw materials increased at the strongest rate in nearly eight years. The final au Jibun Bank Japan Manufacturing Purchasing Managers’ Index (PMI) in January rose to 55.4 on a seasonally adjusted basis, up from a 54.6 flash reading and the previous month’s final of 54.3. That marked the fastest growth since February 2014 and the 12th straight month of expansion in manufacturing activity. “Japanese manufacturers entered the new year in strong spirits,” said Usamah Bhatti, economist IHS Markit, which compiles the survey. “Supply chain disruption remained widespread at the start of 2022, however, with a further sharp lengthening of delivery …