How the Time of Interviews Affects Estimates of Income and Wealth

In the Survey of Household Income and Wealth (SHIW) conducted by the Bank of Italy, the flow variables (income and consumption) refer to the year preceding the interview while the stock variables (household composition and net wealth) refer to the end of the year. However, there are some exceptions that may produce effects on the estimates but that are not usually taken into account. What is more, the time of year of the interviews may affect the composition of the sample (wealthier families may be less available in summer or during holiday periods). We quantify the possible effects of these factors on the estimates of household income and wealth and propose an adjustment method