BEIJING, Sept 15 (Reuters) - China’s industrial output grew 5.3% in August from the same period a year ago, narrowing from a 6.4% increase in July, while retail sales growth slowed significantly, official data showed on Wednesday. The growth of industrial production missed expectations for a 5.8% year-on-year increase in a Reuters poll of analysts. Retail sales rose 2.5% from a year earlier, the slowest pace since August 2020. Analysts in the poll had expected them to grow 7.0% in August after rising 8.5% in July. Fixed asset investment increased 8.9% in the first eight months from a year earlier, just missing expectations for a 9.0% rise and compared with a 10.3% jump in January-July. The Chinese economy made a remarkably strong revival from a coronavirus-led slump, but momentum has slowed over the past few months as businesses grapple with sporadic COVID-19 outbreaks, supply bottlenecks and high raw materials costs. (Reporting by Liangping Gao and Gabriel Crossley; Editing by Sam Holmes)