Index of Eight Core Industries: What It Measures and Why It Matters

The latest data on the Index of Eight Core Industries shows that these key sectors together grew just 0.5% in May 2026, one of the weakest readings in nearly two years. Over the full financial year 2025-26, the index grew by about 1.1%, pointing to slow momentum in India's most basic industrial sectors.

The Index of Eight Core Industries (ICI) measures the combined output of eight basic industries that form the backbone of the economy. These eight are: coal, crude oil, natural gas, refinery products, fertilizers, steel, cement and electricity. Because these industries supply inputs to many other sectors, the index is treated as an early signal of overall industrial health. It is also an important part of the wider Index of Industrial Production (IIP), making up a large share of its total weight.

The May 2026 data showed weakness in several of these sectors. Domestic crude oil and natural gas output continued a long run of contraction, while coal production fell sharply. The fertilizer sector also shrank, by about 0.9%, though this decline was smaller than in earlier months. Lower domestic production of crude and gas means the country has to rely more on imports to meet demand.

For India, the core industries index matters because steady output in coal, oil, steel, cement and power is essential for construction, manufacturing, transport and energy security. Weak growth in these sectors can slow down the broader economy and raise dependence on imports.

For exam aspirants, the Index of Eight Core Industries, its eight components, and its link to the Index of Industrial Production are frequently tested topics in Economy and current affairs.