PDF《香港统计月刊》

香港统计月刊Hong Kong Monthly Digest of Statistics 二??三?三月 March

2003 专题文章 Feature Article 经季节性调整的消费物价指? Seasonally Adjusted Consumer Price Indices 香港统计月刊 二零零三年三月 FA1 Hong Kong Monthly Digest of Statistics March

2003 经季节性调整的消费物价指数 Seasonally Adjusted Consumer Price Indices 消费物价指数涵盖的商品和服务中 , 部分会受到季节性因素所影响 .

换句话说, 这些消费项目的价格在年中的某些月份较高,而在其余的月份则较低.透过统 计方法,可将明显和稳定的季节性差异从消费物价指数原来数列中剔除,从而 更清楚地看到物价的基本趋势. 本文旨在介绍经季节性调整的消费物价指数的特性和编制方法,探讨其应用, 并分析有关数诮甑谋涠榭. Among the commodities and services covered by the Consumer Price Index (CPI), some may be affected by seasonal factors. In other words, the prices of these consumer items are relatively high in certain months of a year but relatively low in the remaining months. Through the application of statistical methods, clear and stable seasonal variations can be removed from the original series of the CPI so that the underlying price trend can be revealed more distinctly. This article aims to introduce the features and compilation method of the seasonally adjusted CPI and explore its applications. It also provides an analysis on the movements of the data concerned in recent years. 如对本文有任何查询,请致电政府统计处消费物价指数组 (

电话:2805 6401). If you have any enquiries on this article, please call Consumer Price Index Section, Census and Statistics Department (Tel. :

2805 6401). 香港统计月刊 二零零三年三月 FA2 Hong Kong Monthly Digest of Statistics March

2003 经季节性调整的消费物价指数 Seasonally Adjusted Consumer Price Indices 1. 引言 1. Introduction 1.1 政府统计处按月编制消费物价指数,以 量度住户普遍所购买的消费商品及服务的价 格水平随着时间而变动的情况.在分析物价变 动时,通常以消费物价指数的按年变动率来反 映消费者所面对的通货膨胀.但这变动率只能 反映物价与一年前的比较. 1.1 The Census and Statistics Department compiles the Consumer Price Index (CPI), which measures the changes over time in the price level of consumer commodities and services generally purchased by households, on a monthly basis. In analyzing price movements, it is common to refer to the year-on-year rate of change in the CPI, which reflects the inflation faced by the consumers. Yet, it only reflects the changes in prices compared with those a year ago. 1.2 若需要分析较近期的物价趋势,应参考 按月变动率.然而,消费物价指数原来数列会 受到季节性因素的影响,不及经季节性调整的 消费物价指数般有效反映按月变动情况. 1.2 If the recent price trend has to be analyzed, it is better to make reference to the month-to-month rate of change. However, the original CPI series is affected by seasonal factors and is not as effective as the seasonally adjusted series in reflecting month-to- month changes. 1.3 本文旨在介绍经季节性调整的消费物价 指数的特性和应用,并分析有关数诮甑 变动情况. 1.3 This article aims to introduce the features and applications of the seasonally adjusted CPI. It also provides an analysis on the movements of the data concerned in recent years. 2. 概念架构 2. Conceptual Framework 2.1 消费物价指数的变动,可分为几个基本 组成部分: 2.1 The movements of the CPI can be broken down into a number of basic components: (i) 趋势周期是指长期基本变动,它主要受 到持续的社会和经济基础因素所影响.长期趋 势通常有周期性的高低变动,每个周期内所发 生的一连串转变通常跨越一年以上的时间.物 价跟大部分其他经济数谎,它的周期性变 动与经济的膨胀和收缩有很大的关系. (i) Trend-cycle refers to the underlying change over a long period of time, which is mainly subject to the sustaining social and economic fundamentals. The long-run trend is often characterized by cyclical up and down movements. A sequence of changes within each cycle generally occurs over a time span of more than one year. Like most of the other economic data, the cyclical change of prices has strong relationship with economic expansion and contraction. (ii) 季节性差异是指有规则地於每年相同的 期间出现的变动.它们基本上源自气候的转变 及假期的影响. (ii) Seasonal variations refer to movements that tend to repeat itself within a year in a regular manner. They are basically originated from changes in climatic conditions and impacts of holidays. (iii) 不规则波动是指有别於季节性差异而非 重复性的短期变动.它们可能是受到短暂活动 (iii) Irregular fluctuations refer to short-term movements that are different from the seasonal variations and are of non-repetitive nature. They 香港统计月刊 二零零三年三月 FA3 Hong Kong Monthly Digest of Statistics March