This equation computes your tax rate based on your gross income and the computed tax owed.

Usage

This is a quick and dirty way to estimate your tax rate in the future if nothing significant has changed since you last filed your taxes.  If your income, dependents, deductions and other elements of your tax return are pretty much the same, you reasonably assume your tax rate from year to year will be relatively the same.  So, the tax rate can be computed as the ratio of the tax you owed on a previous tax filing to the gross income reported on the same tax return.