The Laffer Curve is the simple notion that higher tax rates don’t necessarily generate as much loot as politicians expect because taxpayers have less incentive to earn and/or report income.

And it works in both directions. Lower tax rates don’t lose as much revenue as politicians fear because better tax policy leads to more taxable income.

In a few cases, higher tax rates may even lose revenue and lower tax rates may generate additional receipts. The IRS collected a lot more tax from upper-income taxpayers, for instance, after Reagan slashed the top tax rate from 70 percent to 28 percent.

Over the past few years, I’ve shown lots of evidence from around the world (England, Spain, and France) and in various states (Illinois, Oregon, Florida, Maryland, and New York) to make the case that it is foolish to ignore the Laffer Curve. Not surprisingly, leftists never seem to learn.

More recently, I’ve explained why Obama’s class-warfare tax policy is especially misguided because of Laffer Curve effects.

But I sometimes wonder whether I make any progress with these arguments. Maybe I’m being too much of a wonk? Perhaps I need an example that strikes a chord with regular people.

I don’t know if that’s true, but let’s give it a try. I now have an example of the Laffer Curve for the MTV audience. Best of all, the story is from USA Today.

The IRS got red-faced trying to collect the new tanning tax, burning a hole in estimates on how much the levy would bring in to federal coffers, a new report said Thursday. …Tanning tax receipts for that nine-month period totaled $54.4 million, the report found. That was below projections by the Congressional Joint Committee on Taxation, which had estimated the tax would raise $50 million in the last three months of fiscal year 2010 and $200 million for the full 2011 fiscal year.

Supply-Side Snooki?

Let’s deconstruct the numbers from the article. The Joint Committee on Taxation estimated that this new “Snooki” tax (part of the awful Obamacare legislation) was going to raise about $50 million every three months.

Yet during the first nine months, the tax raised just $54.4 million, not $150 million.

To be fair, some of this huge revenue shortfall may be a result of short-run factors associated with levying a new tax, but does anyone think the actual revenues will match the JCT’s estimates at any point in the future? If you think that will happen, get in touch with me so we can make a friendly wager.

Why am I willing to put my money where my mouth is? Simple, the government’s revenue estimators have been consistently wrong for decades because they use models that assume tax policy has no impact on economic performance.

Just in case you think I’m exaggerating, watch this video.

This is why I said last year that reforming the biased methodology at JCT was an important test of whether the GOP was genuinely on the side of taxpayers.