What's the likelihood that your income tax return will be audited this year by the Internal Revenue Service?

The short answer: not very.

In 2014, the IRS audited only 1% of all individual income tax returns for the preceding year. And if you exclude returns that included business or self-employment income, the odds fell to just 0.4%.

A longer version of this answer: It depends in part on how much money you earned during the taxable year.

If you dig into the latest numbers from the IRS (covering the 2013 tax year), you see that the likelihood your return will be singled out for an audit is a function of your adjusted gross income -- that is, your gross income minus business expenses, health savings account contributions, and a handful of other deductions.

The likelihood you'll be audited is greatest if you either earn no money or you earn a lot:

Taxpayers with $0 in adjusted gross income or less have a 6.04% chance of being audited. How could you have a negative adjusted gross income? According to the IRS, "AGI may be less than zero when a taxpayer reports losses or statutory adjustments that exceed total income."

Let's say, for instance, that you claim business expense deductions that more than offset your gross income. In that situation, the IRS would be wary that you were indeed carrying on a bona fide trade or business.

On the other side of the spectrum, if you earn $10 million or more in adjusted gross income, then you have a nearly 1-in-4 chance of being selected for an audit. Those aren't great odds, but, then again, if you make more than $10 million a year, then you can probably afford to have someone else deal with the headache of an audit.

It's in the middle, in turn, where most of us fall. And the odds there are much closer to the 1% audit rate that governs all individual income tax returns.

If you earn anywhere between $25,000 and $200,000 a year, then the likelihood that the IRS will single out your return is between 0.58% and 0.77%. The lowest likelihood, based on adjusted gross income alone, is for taxpayers earning between $75,000 and $100,000.

This shouldn't be interpreted as a license to cheat on your taxes if you fall within one of the less-examined income classes, as doing so could trigger red flags and cause your return to fall into the small minority of filings that the IRS selects. Among the most common red flags are failing to report all of your taxable income, taking higher-than-average deductions, claiming outsized charitable deductions, and failing to report a foreign bank account. Doing any of these will skew the odds more in favor of an audit irrespective of income.

At the end of the day, however, assuming that you avoid any of these triggers, the graph above shows that the likelihood that your return will be audited is relatively minuscule. Knowing this should make the process of filing your taxes much less worrisome.