Awareness Article # 9 – INFLATION
What is inflation?
Inflation rate of a country is the rate at which prices of goods and services
increase in its economy. It is an indication of the rise in the general level of
prices over time. Since it’s practically impossible to find out the average change in prices of all the goods and services traded in an economy (which would give
comprehensive inflation rate) due to the sheer number of goods and services
present, a sample set or a basket of goods and services is used to get an
indicative figure of the change in prices, which we call the inflation rate.
? India uses the Wholesale Price Index (WPI) to calculate and then
decide the inflation rate in the economy.
? Most developed countries (UK, US, JAPAN and CHINA) use the Consumer
Price Index (CPI) to calculate inflation.
What is WPI?
WPI is the index that is used to measure the change in the average price level of goods traded in wholesale market. In India, a total of 435 commodities data on price level is tracked through WPI which is an indicator of movement in
prices of commodities in all trade and transactions. It is also the price index
which is available on a weekly basis with the shortest possible time lag only two
weeks. The Indian government has taken WPI as an indicator of the rate of
inflation in the economy.
What is CPI?
CPI is a statistical time-series measure of a weighted average of prices of a
specified set of goods and services purchased by consumers. It is a price
index that tracks the prices of a specified basket of consumer goods and
services, providing a measure of inflation.
How WPI is calculated?
In this method, a set of 435 commodities and their price changes are used for the calculation. The selected commodities are supposed to represent various
strata of the economy and are supposed to give a comprehensive WPI value for
WPI is calculated on a base year and WPI for the base year is assumed to
be 100. To show the calculation, let’s assume the base year to be 1970. The
data of wholesale prices of all the 435 commodities in the base year and the
time for which WPI is to be calculated is gathered.
Let's calculate WPI for the year 1980 for a particular commodity, say wheat. Assume that the price of a kilogram of wheat in 1970 = Rs 5.75 and in 1980 =
The WPI of wheat for the year 1980 is,
(Price of Wheat in 1980 – Price of Wheat in 1970)/ Price of Wheat in 1970 x 100
i.e. (6.10 – 5.75)/5.75 x 100 = 6.09
Since WPI for the base year is assumed as 100, WPI for 1980 will become 100
+ 6.09 = 106.09.
In this way individual WPI values for the remaining 434 commodities are
calculated and then the weighted average of individual WPI figures are found
out to arrive at the overall Wholesale Price Index. Commodities are given
weight-age depending upon its influence in the economy.
How is Inflation rate calculated?
If we have the WPI values of two time zones, say, beginning and end of year,
the inflation rate for the year will be,
(WPI of end of year – WPI of beginning of year)/WPI of beginning of year x 100
For example, WPI on Jan 1st 1980 is 106.09 and WPI of Jan 1st 1981 is
109.72 then inflation rate for the year 1981 is,
(109.72 – 106.09)/106.09 x 100 = 3.42% and we say the inflation rate for the
year 1981 is 3.42%.
Since WPI figures are available every week, inflation for a particular week is
calculated based on the above method using WPI on the later week and WPI on
the previous week. This is how we get weekly inflation rates in India.
Characteristics of WPI
Following are the few characteristics of Wholesale Price Index
1. WPI uses a sample set of 435 commodities for inflation calculation 2. The price from wholesale market is taken for the calculation 3. WPI is available for every week
4. It has a time lag of two weeks, which means WPI of the week two weeks
back will be available now.
Disadvantages of WPI
Following are the disadvantages of Wholesale Price Index
1. India is the only major country that uses a wholesale index to measure
inflation. Most countries use the CPI as a measure of inflation, as this
actually measures the increase in price that a consumer will ultimately
have to pay for.
2. It pointed out that WPI does not properly measure the exact price rise an
end-consumer will experience because, as the same suggests, it is at the
3. The main problem with WPI calculation is that more than 100 out of the
435 commodities included in the Index have ceased to be important from
the consumption point of view.
4. India constituted the last WPI series of commodities in 1993-94; but has
not updated it till now that economists argue the Index has lost relevance
and can not be the barometer to calculate inflation. 5. WPI is supposed to measure impact of prices on business. But India uses
it to measure the impact on consumers. Many commodities not consumed
by consumers get calculated in the index. And it does not factor in
services which have assumed so much importance in the economy.
Why India is not shifting to CPI ?
? In India, there are four different types of CPI indices, and that makes
switching over to the Index from WPI fairly 'risky and unwieldy.' The four
CPI series are: CPI Industrial Workers; CPI Urban Non-Manual Employees;
CPI Agricultural labourers; and CPI Rural labour.
? The CPI cannot be used in India because there is too much of a lag in
reporting CPI numbers.
? The WPI is published on a weekly basis and the CPI, on a monthly basis.
And in India, inflation is calculated on a weekly basis.