Now that Congress has postponed repealing and replacing ObamaCare, they’re moving on to tax reform. Let’s hope they can get their act together, because tax reform is one of the keys to revitalizing the economy. The IRS tells us that in 2015, just three categories of taxes made up 80 percent of all federal revenue, with borrowing to cover the deficit providing another 12 percent. The three categories were personal income taxes at 42 percent, “Social Security, Medicare, and unemployment and other retirement taxes” at 29 percent, and corporate income taxes at 9 percent. So, which of these taxes should tax reformers focus on if they want to rev up the economy?

Since you asked, I’ll tell you: it’s the corporate income tax. Yes, the corporate income tax provides much less revenue than the personal income tax. But the corporate income tax, with all its red tape, is holding back business, and many economists will confirm that. If Congress had to choose between doing corporate income tax reform and personal income tax reform, the choice would be clear: do corporate tax reform.

The red tape corporations contend with is the Tax Code’s myriad exceptions. Exceptions are the adjustments, deductions, exemptions, writeoffs, and loopholes in the Tax Code that allow a taxed entity to pay at a rate that is lower than the statutory rate, and perhaps not even pay at all. But American business must take advantage of these exceptions because the statutory tax rate on corporate income in America is among the highest in the world.

Dealing with the Tax Code is expensive for corporations, making them hire extra accountants, lawyers, and financial strategists. And then they hire lobbyists to wrangle yet more exceptions out of Congress. The complexity of the Tax Code is nothing if not a huge drag on the economy costing untold billions each year. For a revenue-neutral reform, Congress could completely eliminate all exceptions in the Tax Code that affect corporations and set the new statutory rates to the current effective rates.

However, the various sectors of the economy pay at rather different effective rates. Also, each sector of the economy has exceptions that only affect it. Consider this: each sector of the economy should have its own tax rate.

The same “radical” reform I’m advocating for the corporate income tax could be used for the personal income tax. But we should be leery about what Congress might do if they again fiddle with the personal income tax, as most American are paying less in income taxes than at just about any time since the inception of the income tax in 1913. The talk of “middle class tax cuts” is absurd. The effective rate for the Fourth Quintile, the next-to-highest income cohort, was 6.1 percent in 2013 (to verify that, see page 12 from the CBO). Nonetheless, there are inequities in the personal income tax that need addressing.

The IRS in Historical Table 3 keys off of AGI (i.e. adjusted gross income) to show tax rates. The rightmost section of Table 3 is “Tax as a percentage of AGI.” What one sees all the way over on the right side of Table 3 is that in 2013, such tax rates had “discontinuities.” That is, as incomes go up one does not always see gradually rising tax rates, sometimes the rates go down. Indeed, those whose AGI was $10,000,000 or more, had an average tax rate (26.2 percent) around three percentage points below those whose AGI was in the $1M-$10M range.

One thing one must be aware of when looking at any data is how it was derived. The better method to calculate tax rates is to key off of “comprehensive income,” i.e. “gross income,” which is what the CBO does. The CBO lists the average tax rate for all individual income taxpayers in 2013 as 9.2 percent, whereas the IRS lists it in Table 3 as 14.7 percent. The huge difference is due in part to what the two agencies use as their bases: gross income versus adjusted gross income. To see the steep progressivity of the personal income tax one needs to use gross income, not AGI, to figure effective tax rates. One also needs to include all income earners, regardless of whether they pay taxes or not, which I don’t believe Table 3 does, as it is only for “Returns showing total income tax.”

There are a few folks in America who earn more than a billion bucks in a year. Consider two hedge fund managers who both earn an even $1B. If one of them has an effective tax rate that is 0.1 percent higher than the other, he would owe the IRS $1,000,000 more in personal income tax than the other guy with the same income. That’s what a silly tenth of a percent can do in the upper reaches of the income spectrum. Some may think: So what, he’s a billionaire, he can afford it. Right, but the other billionaire who’s paying a million bucks less in tax can also afford it. If taxpayers with modest incomes have a soak-the-rich-because-they-can-afford-it attitude, then they shouldn’t expect much sympathy if they pay taxes at much higher rates than others in their own income bracket.

I’ve been using “anomaly” to refer to individuals who pay income taxes at much higher effective rates than the others in their brackets. For a recent article, I found one such anomaly by preparing the tax return of an earner of the median income who could take only the standard deduction, and who would have had an effective rate 4.74 times the average of the Middle Quintile. (An “anomaly” is something that’s unusual, i.e. not average. It’s akin to a term from statistics that seems to be increasingly used by the media: “outlier.” An outlier is a “value far from most others in a set of data,” “an extreme case or exception.”)

If one believes, as I do, in the possibility of a personal income tax system of graduated “real” tax rates that rise in tandem with rising incomes, then one will be eager to read what Congress is going to do, if anything, about all the anomalies they’ve created. Surely, that ought to be a part of tax reform.

One of the big considerations in tax reform is that decades ago the personal income tax, of all things, began to be used to distribute welfare. That’s why the bottom half of income earners pay so little. In recent years the bottom half has provided less than 3 percent of income tax revenue, and the bottom 40 percent has had a negative income tax rate. Any tax rate cut for these people would only serve to shunt more welfare to them. The only earners in the bottom half who actually pay taxes are anomalies, and they can have effective rates higher than the average of those at about the 90th percentile. What’s Congress going to do about them?

Democrats are always moaning about inequality, even though inequality is the nature of the world and will always be with us. But the Tax Code produces inequalities that can be easily quantified with reliable numbers. In fact, these inequalities are numbers: effective tax rates. So for once we have actual inequalities that we might be able to do something about. All we need do to achieve this equality is to end the exceptions in the Tax Code.

But here’s the problem: Congress created these inequalities. And to keep the numbers equal would require Congress to undo much of their handiwork. They would need to delete much of the Tax Code: the part that doles out the exceptions which result in anomalies. But the Tax Code is where Congress gets much of its power. People don’t like giving up power.

We’re wading into what Congress thinks of itself. For years now, regular Americans have thought of Congress about the same way they think of herpes. Nonetheless, some members of Congress think that they should have the power to decide that Americans with equal incomes will pay taxes at significantly different rates, even those with modest incomes. Is Congress wise enough to make that decision? Congress should avoid having to answer that question by preemptively striking out every exception in the Tax Code.

Jon N. Hall of Ultracon Opinion is a programmer/analyst from Kansas City.