Index of Eight Core Industries in India: Coverage, Weights and ISS Exam Questions

The Index of Eight Core Industries (ICI) is a useful industrial indicator for understanding the performance of eight major infrastructure-related industries. It is also important for ISS preparation because the combined index has a direct connection with the Index of Industrial Production (IIP) and requires careful attention to sector weights.

1. What is the Index of Eight Core Industries?

The Index of Eight Core Industries tracks production in eight major industries: Coal, Crude Oil, Natural Gas, Refinery Products, Fertilizers, Steel, Cement and Electricity. The combined index is used as an important indicator of industrial activity.

2. The eight industries and their weights

Under the 2011-12 base series, the eight core industries together account for 40.27% of the IIP weight. The individual weights are fixed within the relevant index series and determine how strongly each industry's movement affects the composite index.

3. How the composite index works

The ICI is a weighted index. A simplified representation is:

When a high-weight industry records a large movement, its contribution to the composite index is greater than that of a low-weight industry with the same percentage movement.

4. ICI and IIP: the important relationship

The eight core industries are major components of India's industrial system and their combined weight in the IIP makes them important for interpreting industrial performance. However, the ICI and IIP are not the same index. ICI covers eight specified core industries, while IIP covers a broader industrial basket and uses its own classification and weights.

5. Reading growth rates correctly

If an industry's index rises from 110 to 115, its index level increased by 5 points, while its percentage growth is 5/110 × 100, approximately 4.55%. This distinction between index-point change and percentage growth is frequently tested in numerical questions.

6. Common mistakes students make

• Calling the ICI the same as IIP.
• Forgetting that the eight industries have different weights.
• Confusing a change in index points with percentage growth.
• Listing the eight industries incorrectly or omitting refinery products.

7. Three important questions

Try each one on your own first, then tap the answer.

Key takeaways

• Know the definition, coverage and official source of the indicator before memorising numbers.
• Separate an index level from its percentage growth or inflation rate.
• Read the reference year, population, classification and weights carefully in numerical questions.
• For current-affairs-linked questions, verify the latest official MoSPI or Government of India release before the examination.