Q.Explain the importance of index numbers in economics, with special reference to the Consumer Price Index.

Index numbers, and the CPI in particular, feed directly into wage decisions, real-income comparisons and government policy.

General importance of index numbers.

1. They give a standard measure of the general price level's rise or fall (inflation/deflation).
2. They form the basis for revising wages and dearness allowance, linking pay to the actual cost of living rather than leaving it unindexed.
3. They allow nominal (money) values to be deflated into real values — real GDP, real wages — which is essential to judge whether people are actually better off, not just earning a larger rupee figure.
4. They assist government policy-making, from monetary policy to subsidy targeting to social-security indexation.
5. They support business forecasting and planning, since firms track price indices to anticipate cost and demand changes. …

Discussing only the GENERAL importance of index numbers without addressing the question's specific request to relate this to the CPI — the CPI's direct link to dearness allowance and real- …