Page 312 - NGTK2018

EXPLANATION OF TERMINOLOGY, CONTENT AND
METHODOLOGY OF SOME STATISTICAL INDICATORS ON PRICE

Consumer price index (CPI) is a relative indicator (measured by %) reflecting
the tendency and change in the price level by time series of market basket of
selected representative consumer goods and services. The basket of goods and
services for measuring CPI consists of popular goods and services which represent
for the population’s consumption are revised and updated every 5 years to be
conformity with population’s consumption structure in each certain period.
Weight for CPI compilation is the expenditure share for item groups in the
total of the household expenditure which is collected from results of Vietnam
Household Living Standard Survey (VHLSS) and used constantly in a 5-year period.
Weighted geometric mean Laspeyres formula is used to compile CPI:
t
n  p  W i 0

I t 0    0 
i

p
i 1  p i 

Where:
I t 0 : CPI in the reference period (t) compared to the constant base
p
period (0);
t
0
p , p : Consumer price of product i in the reference period (t) and in
i
i
the constant base period (0) respectively;
V 0
W i 0  n i : Weight in the constant base period (0);
 V i 0
i 1
0
V : Consumer expenditure in the constant base period (0);
i
n: The number of items/ item groups.

CPI is computed monthly by the following comparative bases: base year,
previous month, same month of the last year, last December and periodical average
for every province/ city directly under the central government.
Gold price index and USD price index are relative indicators (measured by %)
reflecting the tendency and change in the price level of gold and USD by time series
in market.
Gold and USD prices are daily recorded at retail shops, average gold and USD
price is computed as the average of prices of days in a month.
Formula for computing gold and USD price is as follows:
p i t t 1  P i t  100
i P i t 1

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