In the private sector, no business owner would be dumb enough to assume that higher prices automatically translate into proportionately higher revenues. If McDonald’s boosted hamburger prices by 30 percent, for instance, the experts at the company would fully expect that sales would decline. Depending on the magnitude of the drop, total revenue might still climb, but by far less than 30 percent. And it’s quite possible that the company would lose revenue. In the public sector, however, there is very little understanding of how the real world works. Here’s a Reuters story I saw on Tim Worstall’s blog, which reveals that Bulgaria and Romania both are losing revenue after increasing tobacco taxes.

Cash-strapped Bulgaria and Romania hoped taxing cigarettes would be an easy way to raise money but the hikes are driving smokers to a growing black market instead. Criminal gangs and impoverished Roma communities near borders with countries where prices are lower — Serbia, Macedonia, Moldova and Ukraine — have taken to smuggling which has wiped out gains from higher excise duties. Bulgaria increased taxes by nearly half this year and stepped up customs controls and police checks at shops and markets. Customs office data, however, shows tax revenues from cigarette sales so far in 2010 have fallen by nearly a third. …Overall losses from smuggling will probably outweigh tax gains as Bulgaria struggle to fight the growing black market, which has risen to over 30 percent of all cigarette sales and could cost 500 million levs in lost revenues this year, said Bezlov at the Center for the Study of Democracy. While the government expected higher income from taxes in 2010 it has already revised that to the same level as last year. “However, this (too) looks unlikely at present,” Bezlov added. Romania, desperately trying to keep a 20 billion-euro International Monetary Fund-led bailout deal on track, has a similar problem after nearly doubling cigarette prices in 2009 then hiking value added tax. Romania’s top three cigarette makers — units of British American Tobacco, Japan Tobacco International and Philip Morris — contributed roughly 2 billion euros to the budget in taxes in 2009, or just under 2 percent of GDP. They estimate about a third of cigarettes in Romania are smuggled and say this could cost the state over 1 billion euros.

There are two things that are worth noting.

First, every single answer is to the right of the Joint Committee on Taxation. The revenue-estimators on Capitol Hill assume that taxes have no impact on overall economic performance. As such, even confiscatory tax rates have very little impact on taxable income. The JCT operates in a totally non-transparent fashion, so it is difficult to know whether they would say the revenue-maximizing tax rate is 90 percent, 95 percent, or 100 percent, but it is remarkable that a mini-bureaucracy with so much power is so far out of the mainstream (it’s even more remarkable that Republicans controlled Congress for 12 years, yet never fixed this problem, but that’s a separate story).

Second, very few of the respondents made the critically important observation that it should not be the goal of tax policy to maximize revenue. After all, the revenue-maximizing point is where the damage to the overall economy is so great that taxable income falls enough to offset the impact of the higher tax rates. Greg Mankiw of Harvard and Steve Moore of the Wall Street Journal indicated they understood this point since they both explained that the long-run revenue-maximizing rate was lower than the short-run revenue-maximizing rate. But Martin Feldstein of Harvard explicitly addressed this issue and hit the nail on the head.

Why look for the rate that maximizes revenue? As the tax rate rises, the “deadweight loss” (real loss to the economy) rises. So as the rate gets close to maximizing revenue the loss to the economy exceeds the gain in revenue…. I dislike budget deficits as much as anyone else. But would I really want to give up say $1 billion of GDP in order to reduce the deficit by $100 million? No. National income is a goal in itself. That is what drives consumption and our standard of living.

For more information, I think my three-part video series on the Laffer Curve is a good summary of the key issues. I posted them in May 2009, but Cato-at-Liberty has been growing rapidly and many people have not seen them. Part I addresses the theory, and explicitly notes that policy makers should target the growth-maximizing tax rate rather than the revenue-maximizing tax rate. Part II reviews some of the evidence, including analysis of the huge increase in taxable income and tax revenue from upper-income taxpayers following the Reagan tax-rate reductions. Part III looks at the Joint Committee on Taxation’s dismal performance.

The Wall Street Journal has an excellent editorial this morning on the obscure — but critically important — issue of measuring what happens to tax revenue in response to changes in tax policy. This is sometimes known as the dynamic scoring versus static scoring debate and sometimes referred to as the Laffer Curve controversy.

The key thing to understand is that the Joint Committee on Taxation (which produces revenue estimates) assumes that even big changes in tax policy have zero macroeconomic impact. Adopt a flat tax? The JCT assumes no effect on the economic performance. Double tax rates? The JCT assumes no impact on growth.

The JCT does include a few microeconomic effects into its revenue-estimating models (an increase in gas taxes, for instance, would reduce gasoline consumption), but it is quite likely that they underestimate the impact of high tax rates on incentives to work, save, and invest. We don’t know for sure, though, because the JCT refuses to make its methodology public. This raises a rather obvious question: Why is the JCT so afraid of transparency? Here’s some of what the WSJ had to say about the issue, including some comparisons of what the JCT predicted and what happened in the real world.

…it’s worth reviewing whether Joint Tax estimates are accurate. This is especially important now, because President Obama and Democrats in Congress want to allow the 2003 tax cuts to expire on January 1 for individuals earning more than $200,000. The JCT calculates that increasing the tax rates on capital gains, dividends and personal income will raise nearly $100 billion a year. …we are not saying that every tax cut “pays for itself.” Some tax cuts—such as temporary rebates—have little impact on growth and thus they may lose revenue more or less as Joint Tax predicts. Cuts in marginal rates, on the other hand, have substantial revenue effects, as economic studies have shown. …So how well did Joint Tax do when it predicted a giant revenue decline from the 2003 investment tax cuts? Not too well. We compared the combined Congressional Budget Office and Joint Tax estimate of revenues after the 2003 tax cuts were enacted with the actual revenues collected from 2003-2007. In each year total federal revenues came in substantially higher than Joint Tax predicted—$434 billion higher than forecast over the five years. …As for capital gains tax receipts, they nearly tripled from 2003 to 2007, even though the capital gains tax rate fell to 15% from 20%. Yet the behavioral models that Mr. Barthold celebrates predicted that the capital gains cuts would cost the government just under $10 billion from 2003-07 when the actual capital gains revenues over five years were $221 billion higher than JCT and CBO predicted. …Estimating future federal tax revenues is an inexact science to be sure. Our complaint is that Joint Tax typically overestimates the revenue gains from raising tax rates, while overestimating the revenue losses from tax rate cuts. This leads to a policy bias in favor of higher tax rates, which is precisely what liberal Democrats wanted when they created the Joint Tax Committee.

All of the revenue-estimating issues are explained in greater detail in my three-part video series on the Laffer Curve. Part I looks at the theory. Part II looks at the evidence. Part III, which can be watched below, analyzes the role of the Joint Committee on Taxation and speculates on why the JCT refuses to be transparent.

Smart statists understand that there are very strong Laffer Curve effects at the top of the income scale since investors and entrepreneurs have considerable ability to control the timing, level, and composition of their income. So if higher tax rates on upper-income taxpayers don’t collect much revenue, why is the left so insistent on class-warfare taxation? The answer, I think, is that soak-the-rich taxes are a “loss-leader” that politicians impose in order to pave the way for higher taxes on the middle class. Indeed, I made this point in my video on class warfare taxation, and noted that are not enough rich people to finance big government. As such, politicians that want to tax the middle class hope to soften opposition among ordinary people by first punishing society’s most productive people. We already know that tax rates on the so-called rich will jump next January thanks to higher income tax rates, higher capital gains tax rates, more double taxation of dividends, and higher death taxes. Now the politicians are preparing to drop the other shoe. Excerpted below is a blurb from the Washington Post about a member of the House Democratic leadership urging middle-class tax hikes, and let’s not forgot all the politicians salivating for a value-added tax.

Tax cuts that benefit the middle class should not be “totally sacrosanct” as policymakers try to plug the nation’s yawning budget gap, House Majority Leader Steny Hoyer (D-Md.) said Monday, acknowledging that it would be difficult to reduce long-term deficits without breaking President Obama’s pledge to protect families earning less than $250,000 a year. Hoyer, the second-ranking House Democrat, said in an interview that he expects Congress to extend middle-class tax cuts enacted during the Bush administration that are set to expire at the end of this year. But he said the extension should not be permanent. Hoyer said he plans to call for a “serious discussion” about the affordability of the tax breaks. …The overarching point in Hoyer’s remarks is the need for a bipartisan plan that includes spending cuts and tax increases, in the tradition of deficit-reduction deals cut under former presidents George H.W. Bush and Bill Clinton. Drafting such a plan would require a reexamination of tax cuts enacted in 2001 and 2003, Hoyer says — cuts that benefited most taxpayers.

David Ranson had a good column earlier this week in the Wall Street Journal explaining that federal tax revenues historically have hovered around 19 percent of gross domestic product, regardless whether tax rates are high or low. One reason for this relationship, as he explains, is that the Laffer Curve is a real-world constraint on class warfare tax policy. When politicians boost tax rates, that motivates taxpayers to earn and/or report less income to the IRS:

The feds assume a relationship between the economy and tax revenue that is divorced from reality. Six decades of history have established one far-reaching fact that needs to be built into fiscal calculations: Increases in federal tax rates, particularly if targeted at the higher brackets, produce no additional revenue. For politicians this is truly an inconvenient truth. …tax revenue has grown over the past eight decades along with the size of the economy. It illustrates the empirical relationship first introduced on this page 20 years ago by the Hoover Institution’s W. Kurt Hauser—a close proportionality between revenue and GDP since World War II, despite big changes in marginal tax rates in both directions. “Hauser’s Law,” as I call this formula, reveals a kind of capacity ceiling for federal tax receipts at about 19% of GDP. …he tax base is not something that the government can kick around at will. It represents a living economic system that makes its own collective choices. In a tax code of 70,000 pages there are innumerable ways for high-income earners to seek out and use ambiguities and loopholes. The more they are incentivized to make an effort to game the system, the less the federal government will get to collect.

Several people have asked my opinion about the piece. I like the column, of course, but I’m not nearly so optimistic that 19 percent of GDP represents some sort of limit on the federal government’s taxing power. There are many nations in Europe with tax burdens closer to 50 percent, for instance, so governments obviously have figured how to extract much higher shares of national output. Part of the difference is because America has a federal system, and state and local governments collect taxes of about 10 percent of GDP. That still leaves a significant gap in total tax collections, though, so the real question is why American politicians are not as proficient as their European cousins at confiscating money from the private sector?

One reason is that European countries have value-added taxes, which are a disturbingly efficient way of generating more revenue. So does this mean that “Hauser’s Law” will protect us if politicians are too scared to impose a nationwide sales tax? That’s certainly a necessary condition for restraining government, but probably not a sufficient condition. If you look at the table, which is excerpted from the OECD’s annual Revenue Statistics publication, you can see that nations such as New Zealand and Denmark have figured out how to extract huge amounts of money using the personal and corporate income tax.

In some cases, tax rates are higher in other nations, but the main factor seems to be that the top tax rates in other nations are imposed at much lower levels of income. Americans don’t get hit with the maximum tax rate until our incomes are nine times the national average. In other nations, by contrast, the top tax rates take effect much faster, in some cases when taxpayers have just average incomes. In other words, European nations collect a lot more money because they impose much higher tax rates on ordinary people. Here’s a chart I put together a few years ago for a paper I wrote for Heritage (you can find updated numbers in Table 1.7 of this OECD website, but the chart will still look the same).

Europeans also sometimes impose high tax rates on rich people, but this is not the reason that tax receipts consume nearly 50 percent of GDP in some nations. Rich people in Europe, like their counterparts in America, have much greater ability to control the amount of taxable income that is earned and/or reported. These “Laffer Curve” responses limit the degree to which politicians can finance big government on the backs of a small minority.

But class-warfare tax rates on the rich do serve a very important political goal. Politicians understand that ordinary people will be less likely to resist oppressive tax rates if they think that those with larger incomes are being treated even worse. Simply stated, higher tax rates on the rich are a necessary precondition for higher tax rates on average taxpayers.

For “Hauser’s Law” to be effective, this means proponents of limited government need to fight two battles. First, they need to stop a VAT. Second, they need to block higher tax rates on the so-called rich in order to prevent higher tax rates on the middle class.