Korea's industrial output expanded in September from a month earlier at the fastest pace in more than 15 years, led by chips, data showed Friday, with retail sales and facility investment also gaining ground. Industrial production rose 3 percent on-month in September, according to data from the Ministry of Data and Statistics. It marked the sharpest gain since the 3.4 percent increase posted in March 2011. It also marked the first time since June that the three major indicators increased simultaneously. The overall industrial output grew on-month in June by 2.6 percent, which narrowed to 0.1 percent in July. In August, the output shed 1.2 percent. Output in the mining and manufacturing sector, a key pillar of the economy, soared 9 percent, led mostly by semiconductor production, which jumped 19.2 percent. The increase in chip output was the largest since the 28.2 percent gain posted in February. The data ministry attributed the gains to increased production of memory chips, such as dynamic random access memory (DRAM) products. Other major gainers included the automobile industry, where out