NCERT Book Class 11 Economics (Statistics for Economics) Chapter 7 Index Numbers

CHAPTER

Index Numbers

commodities have changed. Some
Studying this chapter should items have become costlier, while others
enable you to: have become cheaper. On his return
• understand the meaning of the from the market, he tells his father
term index number; about the change in price of the each
• become familiar with the use of and every item, he bought. It is
some widely used index bewildering to both.
numbers; The industrial sector consists of
• calculate an index number; many subsectors. Each of them is
• appreciate its limitations. changing. The output of some
subsectors are rising, while it is falling
1. INTRODUCTION in some subsectors. The changes are
not uniform. Description of the
You have learnt in the previous chapters individual rates of change will be
how summary measures can be difficult to understand. Can a single
obtained from a mass of data. Now you figure summarise these changes?
will learn how to obtain summary Look at the following cases:
measures of change in a group of
related variables. Case 1
Rabi goes to the market after a long An industrial worker was earning a
gap. He finds that the prices of most salary of Rs 1,000 in 1982. Today, he