.TH tax "" "" "/rdb Command"
.PC "Compute tax from income and tax table"
\fBtax \fIincome \fB< \fItaxtable\fR
.PP
.II "table^compute tax"
The command
.B tax
reads tax-table information from
.I taxtable
and computes taxes from it.
.I income
is the income you wish to check.
.I taxtable
must be in the three-column format shown in the following example.
.PP
.B tax
writes to the standard output
the computed tax rounded off to the nearest dollar.
.SH Example
The following table,
.BR X83 ,
holds the federal income tax for single taxpayers for 1983 (Schedule X):
.DM
income  tax     percent
------  ---     -------
2300    0       11
3400    121     12
4400    251     15
6500    566     15
8500    866     17
10800   1257    19
12900   1656    21
15000   2097    24
18200   2865    28
23500   4349    32
28800   6045    36
34100   7953    40
41500   10913   45
55300   17123   50
.DE
.PP
If your taxable income is $20,000, type the following:
.DM
	tax 20000 < X83
.DE
.PP
.B taxtable
writes the following to the standard output:
.DM
   3369
.DE
.PP
That is, according to the data in
.BR X83 ,
a single person with an income of $20,000 in 1983 owed the IRS
$3,369.
.PP
You can also catch the output in a shell variable, like this:
.DM
	TAX=`tax 20000 < X83`
.DE
.PP
This initializes environmental variable
.B TAX
to
.BR 3369 .
You can now use
.B TAX
to write the tax into a table.
For example:
.DM
	compute "line == 35 { value = $TAX }" < form1040
.DE
.PP
Note that this command
uses the quotation mark (") instead of the apostrophe ('),
because we want the shell to substitute the value of tax where we
have typed $TAX.
To quote something within quotation marks ("), you
must use apostrophes (').
.SH Notes
Please note that the tax tables included with
.B /rdb
are for 1987.
Mark Williams Company makes no claim as to their accuracy, or their
usefulness in computing current taxes.
.I "Caveat utilitor!"