FAMILY-BASED STATISTICS OF INCOME
For many years the Utah State Tax Commission has produced detailed statistical reports based on federal tax returns filed by residents of the state. These reports have always been return-based, by which we mean that the primary unit of analysis was the tax return. One problem with this approach, for example, was that minors working part-time were not grouped with their families and thus, our statistics always showed a high number of returns in the low-income classes. Since 1993, we have also produced a Family-Based Statistics of Income
This report groups returns into larger units, such as households or families. We group returns that show
the same last name, ZIP Code, and first part of the address into a unit, generally a family. This groups
minors with their parents, if they use the same name and address. It also groups a married couple living with
the husband's parents (same last name). However, it would not group a married couple living with the wife's
parents (different last names).
This publication reports for the data for the State, for counties, for cities and ZIP Codes. We have also included a table reporting mean and median incomes (AGI) for cities, using both a return approach and a "family" approach. We have produced a similar table for counties for the first time.
THE COUNTY RESULTS
We believe the value of this report is in the detailed tables. Nonetheless, we have prepared a summary table
and graph which compare the household perspective with the return perspective by county. The
accompanying tables give, for the state as a whole, and for each county, both the number of returns filed
with the IRS and the number of households our method yields. In addition, it reports per return and per
household data for both adjusted gross income (AGI) and exemptions. For the state as whole, the number
of returns was about 26 percent higher than the number of households; thus the corresponding AGI and
exemptions per household were 26 percent greater than the return values. A quick glance at the table,
reveals the largest differences were in Davis, Morgan, Kane, Utah, and Wasatch counties, where there was
a 30% difference. The smallest differences were in Wayne, Daggett, and Emery counties where the
difference was less than 15%. The median difference was 24%.