Four series of Consumer Price Indices (CPIs) are compiled to reflect the impact of consumer price changes on households in different expenditure ranges. The CPI(A), CPI(B) and CPI(C) are compiled based on the expenditure patterns of households in the relatively low, medium and relatively high expenditure ranges. By aggregating the expenditure patterns of all households covered by the above three indices, a Composite CPI is also compiled to reflect the impact of consumer price changes on the household sector as a whole. The year-on-year rate of change in this index is generally taken to reflect overall consumer price inflation. The CPI(A), CPI(B) and CPI(C) respectively cover some 50%, 30% and 10% of households in Hong Kong. The average monthly household expenditures (in HK$) of these groups in the base period (i.e. October 2014 - September 2015) were $5,500 - $24,499, $24,500 - $44,499 and $44,500 - $89,999 respectively. Taking into account the impact of price changes since the base period, the monthly household expenditure ranges of the CPI(A), CPI(B) and CPI(C) adjusted to the price level of 2016 are broadly equivalent to $5,700 - $25,200, $25,200 - $45,700 and $45,700 - $92,300 respectively, and that of the Composite CPI is broadly equivalent to $5,700 - $92,300.
For information on the 2009/10-based CPI series, please refer to Table 52A, Table E501A and Table E502A. The old 2009/10-based CPI series ceased to be compiled starting from the reference month of January 2017.