The Bank of Italy's first Survey of Household Income and Wealth (SHIW) was conducted in 1965. Twenty–three further surveys have been conducted since then, yearly until 1987 (except for 1985) and every two years thereafter. The interviews for the twenty–fourth survey were completed in the Summer of 1992.
The aim of the SHIW is to gather information concerning the economic behavior of Italian families at the microeconomic level. Data on family income, saving, expenditure for consumer durables and real wealth have been collected since 1966, while the acquisition of details regarding total consumption expenditure started in 1980, essentially to improve internal consistency controls and to facilitate comparison with the Istat expenditure survey.
The methodology used in collecting the data and the definitions of the survey variables underwent several modifications over the years, hampering the possibility of using the survey evidence to perform intertemporal comparisons. The main features and modifications of the SHIW will be described in Section 2, while in Section 3 the results of the studies on the quality of the survey will be briefly presented.
A description of the survey design
The survey unit
The basic survey unit is the “household”, which is defined as a group of individuals linked by ties of blood, marriage or affection, sharing the same dwelling and pooling all or part of their incomes. Persons living in nursing homes for the aged or ill, prisons, or military installations are not included.