I. Main Contents
Data in this chapter show the people’s living conditions and their changes in China, consisting of two parts: integrated urban and rural households survey on income and expenditure and living conditions since 2013, and urban household survey and rural household survey respectively prior to 2012.
II. Sources of Data and Methodology on the Integrated Urban and Rural Household Survey on Income and Expenditures and Living Conditions
The NBS has started integrated household survey since the fourth quarter of 2012. The main contents of the survey include: income and expenditure of the household, and surveys of employment, social security participation, housing, family operation, production investment, and also influence factors of income distribution.
The integrated household survey is conducted by selecting sampled houses randomly, deciding surveyed households, with all households in the province as the population, with stratified sampling, multi-stage sampling, probability sampling in proportion to population scale. 16,000 communities of 1,650 counties in the total country are selected, more than 2 million households in them are surveyed comprehensively, and then on this basis, randomly select about 160,000 households for keeping diaries. Communities and households surveyed rotate regularly.
Survey on Income and Expenditures and Living Conditions is required that the sampling error should not exceed ±1%, with a confidence probability as 95%. Methods of collecting income and expenditure data are keeping diaries of the households, and questionnaires as assistance to collect other relevant data. All survey works are conducted by investigation team of NBS independently. Coding, check, entering of original data are conducted by investigation teams at city level with the same methods and data processing programming, and then basic data are transferred to NBS to tabulate the data.
In terms of the system of Integrated Urban and Rural Households on Income and Expenditures and Living Conditions conducted since 2013, NBS collected accounts of 160,000 households about 12 months, at this basis, NBS tabulated comparable national disposable income and expenditures of urban and rural households.
According to the integrated household survey, main changes of population covered by data of per capita disposable income of urban and rural households: migrant workers resided in urban areas are included in the denominator when calculating per capita disposable income of urban household, migrant workers are not included in denominator when calculating per capita disposable income of rural households; college students of their households are regarded as permanent residents. Main changes of urban household and rural household per capita disposable income and expenditure of new coverage: converted rents of self-owned housing are included when calculating per capita disposable income and expenditure of urban and rural households.
Ⅲ. Sources of Data and Methodology on the Living Conditions of Urban Residents
The sample survey on the urban households was conducted by the Office of Urban Household Surveys of the NBS prior to 2012. The main contents of the survey include persons in the household and the household composition; cash income and expenditure of the household; quantity of major commodities purchased and expenditure; the employment of household members; the housing condition; and the possession of durable consumer goods.
The survey had covered only non-farm households prior to 2001. From 2002 to 2012, the survey covers the households in district areas of all city and county towns.
Sample cities and towns in urban areas are selected by using stratified random sampling method. Firstly, all the urban areas and towns of all provinces (autonomous regions and municipalities directly under the Central Government) are stratified into three strata according to population size: large and medium-sized cities (at and above prefecture level), county cities and county towns; secondly, the sample size is decided by proportion of population in selected stratus to the provincial total; thirdly, cities and towns are arranged in ranking the annual average wages of the employed persons, then with the accumulative population in each city and town sample cities and towns are selected by systematic sampling scheme according to the size of the samples.
The selection of sample households in urban areas is done by two steps: the first step is to have a one-off large sample survey; the second step is to select a small sample from the large sample to be used as regular sample households for diaries.
The large sample survey is conducted for every three years; the objective is to provide sample frame for regular surveys and basic information for data evaluation of regular surveys. In the large sample survey, samples in sample cities and towns are selected by systematic sampling method schemes, such as two-phase sampling and stratifying method, two-stage (multi) method and probability proportional to size (PPS) method. Namely, stratification is done at district level, and then PPS systematic sampling method is used to select sample communities/resident’s committees, finally the same method is used to select dwellings from the selected districts/resident’s committees. In some large cities, three-stage sampling method is used. First, the communities/resident’s committees are selected. Secondly, sample districts are selected. Thirdly, sample dwellings are selected. A survey will be conducted to the large samples or the first phase samples to collect relevant information on household population, persons employed, income and so on. Then grouping is made based on the information collected, small samples or the second phase samples are selected according to proportions which are regular sample households to keep diary.
The national sample included 66,000 households at the end of 2012.
Ⅳ. Sources of Data and Methodology on the Living Conditions of Rural Residents
The sample survey on rural households was organized by the Office of Rural Household Survey of the NBS prior to 2012. The main contents of the survey include the basic condition of rural households, housing conditions, income, consumption expenditure, consumption of major consumer goods and the quantity of durable consumer goods owned.
Sample survey on rural households is conducted by first selecting sampled villages and then selecting households in the selected villages in each province, with all rural households in the province as the population. A combination of various sampling approaches is used to identify a total of 74,000 households selected from 7,000 villages throughout the whole country.
It is required that the sampling error should not exceed ±3%, with a confidence probability as 95%. In order to ensure the accuracy of the survey data on the rural households, two accounts are designed for the respondent households by the Office of Household Survey of the NBS: the cash account and the account on goods in kind. Nearly 10 thousand assistant enumerators have been recruited to help the households keep good accounts and to check on a timely fashion and to and tabulate the data from the survey.
In order to overcome the tedium of respondent households and to ensure that the sample is accurately representative over time and reflects the changing rural social and economic situation, a rotation sampling scheme is implemented, and the complete cycle of rotation is 5 years.