**UTAH INCOME TAX RETURN DATA FOR 1997**

This publication is a rather detailed description
of data from 1997 Utah state income tax
returns. An income tax file is always dynamic,
with late returns, amended returns, and audits
changing the data. This means that in small
ways the results depend on when the data to
be analyzed is captured. This report analyzes
1997 return data as of March 1 of 1998.

**RESIDENCY ISSUES**

State income tax returns include both full- year
residents and non-residents, with the latter
including those who moved in or out during
the year, as well as those who never lived here
but still have income from the state. We have
presented broad summary data for non-residents, but for the most part have not
presented detailed data, since its interpretation
is difficult or meaningless, especially for
statistical distributions.

**STATISTICAL MEASURES**

This year's report is mainly "statistical". The general strategy has been to report statistical points for the most important lines on the state form, with different tables according to the residency and filing status (Married, Single, etc), of the taxpayer. When not using an income breakdown, we have reported percentage deciles, as well as the mean, the median, and the mean for those claiming a non-zero amount. Since the number of returns is the same for each line, we have reported under the non-zero heading the number of returns not reporting zero for a given line. Table 5, rather than using an arbitrary income division which gets outdated over many years, uses income deciles relevant to the group being examined. "Lower income" and "upper income" show the income range.

A brief review of statistical terms for those not using them every day follows:

__The mean__ is the total dollar amount
divided by the number of returns.

__The non-zero mean__ is the mean of
non-zero data.

__The median is the middle value__.

__A decile__ divides the values into tenths.
For example the bottom decile reports
the value dividing the bottom 10
percent from the top 90 percent, or the
sixth decile (p60) divides the bottom
60 percent from the top 40 percent.

We think some of these issues will become
clearer as we examine specific tables.

**THE TABLES**

** Summary table **(page 2) is an excerpt from
table 2, and it shows, for all taxpayers, the
total number using the line, the total amount
claimed, and the average for all taxpayers and
the average for those using the line.

__ The traditional table__ (page 4) reports for all
full-year residents using traditional but
arbitrary income brackets. It reports the
number of returns, the amount of adjusted
gross income, state income taxes, an effective
tax rate and number of exemptions. The table
labeled "calendar year" is for the 1997 returns
only. We produce a similar table near the end
of each year that includes the returns filed in
that year for the previous two years, hoping
that the late returns filed for the tax year two
years ago represent the returns not yet filed for
the one year ago return. For example, the data
produced in late 1997 included 1997 and 1995
returns processed in 1997. We do this to
parallel federal data.

__ Table 1__ reports, for various residency and
filing status groupings, the number of all
returns filed and the deciles for adjusted gross
income. It also reports the 5 percent and 95
percentage point breaks. These decile
groupings are those used to define income
groups on table 5.

__ Table 2__ reports for each of the major lines,
where data is available, various statistical
measures for all taxpayers.

__ Table 3__ is similar to table two, but there is a
breakdown by residency. (

__ Table 4__ is similar to table two, but it only
includes full year residents and there is a filing
status breakdown.

__ Table 5__ reports by filing status for full-year-residents using an income breakdown based on
adjusted gross income deciles. In addition to
the income bracket limits and the number of
non-zero entries, the total amount, the mean
for all taxpayers in the group, the mean for
non-zero entries, and the median are reported.

**UTAH TAXABLE INCOME BRACKETS**.

We are frequently asked about the number of taxpayers and the amount of Utah taxable income that is in each of the current state income tax brackets. The following two tables respond to that issue. For these tables we have collapsed the filing status groups into two, putting heads of households and married joint together, and amalgamating single filers with married filing single. We did this is because the tax brackets are the same for these groups.

__ Table 6__ shows for each of the collapsed
groups, the number of returns and the amount
of taxable income in the lower brackets (all but
the top) and the amount in the top bracket. It
also reports the percent of returns and percent
of taxable income in each bracket for each
group. For example, 40.9 percent of all full
year returns are in the top bracket and file
married joint or head of household; 65.9
percent of all full year taxable income is taxed
at the top rate and belongs to the joint or
household group.