This is the second in a series of quarterly reports based on data from the Survey of Income and Program Participation (SIPP). The first report was issued in September 1984 and presented data on average monthly income, labor force activity, and program participation for the third quarter of 1983. This report presents similar data for October to December of 1983.

The SIPP quarterly report series has been established to make data from the survey available as quickly as possible and to provide information that will serve to supplement those currently available from other statistical series produced by the Bureau of Labor Statistics and the Bureau of Economic Analysis that measure changing economic conditions. The data presented in the quarterly reports differ in one important aspect from those available in these other series. They permit examination of the relationship between household income, participation in government programs, and the labor force activity of household members. More detailed studies of these relationships will be possible when the SIPP longitudinal data base is complete. This data base, which will contain monthly data for the same sample households over a 12-month period, is under development. This quarterly series of reports showing monthly averages will be the main source of estimates of change from SIPP until the longitudinal data are ready.

Several cautions should be noted concerning the estimates shown in the first few reports of this publication series. First, the data in the SIPP quarterly report series will be designated as preliminary until all phases of the data collection and computer processing systems have been tested over at least a 1-year period. Some of the data shown in the first report for the third quarter of 1983 have already undergone revisions. Figures for the third quarter shown in this report reflect those revisions.

Second, it is difficult to interpret some of the changes because the SIPP is the first survey to provide data on monthly changes in income, program participation, and household composition. More observations will be required before factors such as seasonality can be studied and placed in perspective. None of the data in this report have been seasonally adjusted. In addition, other aspects of data collection and processing need to be examined. These include response error, assignment of survey weights, and the accuracy of the imputations for missing survey responses.

Most of the estimates in this report are in the form of monthly averages for the specified quarter and are restricted to the nonfarm population.

The data were collected in interviews conducted during the period from November 1983 to April 1984.