To capture performance of economy in a better way, the government may soon expand the list of core sector infrastructure industries to include natural gas and fertilisers.
Currently, the government evaluates performance of six key sectors -- crude oil, petroleum refinery, cement, electricity, finished steel and coal -- on a monthly basis.
"The additions of two new categories is likely to increase the weight of the core sector to upto 30 per cent in the IIP," a senior official said.
The six infrastructure industries have a weight of 26.7 per cent in the overall Index of Industrial Production.
The official said that most likely, the new core sector data with these two new additions would be released after the launch of IIP with the new base year.
"The new IIP numbers will give the weight for these two categories," the official said adding if the new IIP would be launched on June 10 "we would also launch the new core data on the same day".
The base year for the new IIP series will be changed to 2004-05 from 1993-94 and is expected to be released on June 10.
According to experts,