New Delhi: India's core industrial output rose by 8.5 per cent in April on the back of higher production of electricity, steel and refinery products, official data showed on Tuesday. The gauge for select factory output -- Index of Eight Core Industries (ECI) -- which represents major infrastructure sectors rose by 6.4 per cent in March 2016. The ECI data showed a negative growth of 0.2 per cent in the corresponding month of last year. The index comprises 38 per cent of the total weightage of items included in the Index of Industrial Production (IIP). According to the data furnished by the Ministry of Commerce and Industry, the combined ECI index stood at 176.4 in April 2016. Under the ECI, electricity, steel, refinery products and fertilisers industries reported healthy output, whereas production of crude oil, coal and natural gas declined. Electricity generation, which has the highest weightage of 10.32 per cent in the IIP, augmented by 14.7 per cent in April, as compared with the corresponding month of 2015. Steel production, the second most important component as per weightage of 6.68 per cent, increased by 6.1 per cent in the month under review. Distilling of refinery products, the third most important component as per weightage, rose by 17.9 per cent in April, as compared with the corresponding month of last year. However, extraction of crude oil, which has a 5.21 per cent weightage in IIP, decreased marginally by 2.3 per cent during last month. Further, coal mining, with a 4.38 per cent weightage, slipped by 0.9 per cent last month. In contrast, cement production, which has the weightage of 2.41 per cent, increased by 4.4 per cent in April 2016. The sub-index for natural gas output, with a weightage of 1.71 per cent declined by 6.8 per cent in the month under consideration. Besides, fertiliser manufacturing, which has the least weightage of only 1.25 per cent, surged by 7.8 per cent.