Growth of the country's eight core sector industries slowed to a 13-month low of 1.8 percent in January this year. The core sector industries had expanded by 3.7 per cent in January last year. According to data released by the Commerce and Industry Ministry, crude oil production declined 2.3 percent, and natural gas output dropped 6.6 percent in January this year. Steel and cement output and electricity generation increased during the month under review, but at a slower rate than in January last year. But coal production increased 1.7 percent, petroleum refinery production rose 4.7 percent, and fertilizer output increased 7.1 percent in January this year. During the April 2014 to January 2015 period, the core sector industries grew 4.1 per cent, as against 4 per cent growth in the same period of the previous fiscal.