Our country's economic health has almost always been an accurate barometer of presidential elections. Incumbents win when economic performance is strong, as in Bill Clinton's 1996 re-election, but are voted out when the economy is weak, as when Ronald Reagan defeated Jimmy Carter in 1980. Our current economic weakness suggests that Gov. Mitt Romney should be ahead of President Barack Obama in the polls.

Our country's economic health has almost always been an accurate barometer of presidential elections. Incumbents win when economic performance is strong, as in Bill Clinton's 1996 re-election, but are voted out when the economy is weak, as when Ronald Reagan defeated Jimmy Carter in 1980. Our current economic weakness suggests that Gov. Mitt Romney should be ahead of President Barack Obama in the polls.

But in this campaign, economic growth is not the only major factor influencing voters. Rather, perceptions of inequality are playing a larger role than in the past, reflecting Obama's assertions that the rich do not �pay their fair share of taxes� and that inequality has widened substantially, with the benefits of economic growth accruing only to the few at the top of the economic ladder.

But claims that income inequality has widened substantially in the past three decades are misleading or inaccurate. Most of these claims are drawn from U.S. Census data and are based on an income definition that is a very poor measure of household disposable income, as it excludes major sources of income and taxes.

The excluded income sources include transfer payments (such as food stamps, welfare, Medicaid and public housing), employer-provided fringe benefits (which can be as much as 30 percent of income) and capital gains. But even this flawed measure of inequality showed growth of only about 10.7 percent between 1981and 2010.

A superior measure of income inequality, based on the Census� broadest measure of income � which subtracts taxes and adds in many of the income sources noted above � declined about 2 percent between 1993 and 2009.

Similarly, the widely held view that middle class incomes have been stagnant is wrong. According to the Congressional Budget Office, between 1979 and 2007, inflation-adjusted after-tax income for those between the 40th and 60th income percentiles rose by about 44 percent, while aggregate income rose by about 75 percent.

Do the rich pay their fair share of taxes? Neither the president nor anyone else has offered a generally accepted definition of this, but it is instructive to compare U.S. income-tax rates to those in other advanced countries. A 2008 study by the Organization of Economic Cooperation and Development found that compared to the 24 most advanced countries in the organization (including France, Germany and Sweden), the U.S. income tax system is the most progressive, with a progressivity index that is 22 percent higher than the average for the 24 countries.

In 2009, the top 1 percent of U.S. income earners earned 17 percent of income, but paid 37 percent of income taxes. The top 5 percent earned 32 percent of income but paid 59 percent of taxes, while the bottom 95 percent paid 41 percent of taxes, and the bottom 47 percent paid no income taxes.

Inequality is indeed higher in the U.S. than in many other countries, but some inequality is the natural consequence of America�s high level of economic freedom that has produced a high rate of entrepreneurship and economic growth. Since the 1970s, individuals such as Bill Gates of Microsoft Corp. and Steve Jobs of Apple Inc. became very wealthy by creating remarkable new products and, in the process, created entire new industries and millions of jobs. Inequality is 30 percent lower in Europe, but Europe also has a roughly 30 percent lower per-capita gross domestic product and standard of living.

These facts indicate that we should focus not on income inequality but rather on the equality of economic opportunity so that all Americans can succeed. The employment rate today is lower than when Obama took office, reflecting a job-creation rate that is far too low to give all of our workers these opportunities. The president's proposal to increase taxes on the highest earners � including entrepreneurs � is the wrong policy. It will likely depress job creation even further and lead to an even weaker economy than we have now.

Lee E. Ohanian is professor of economics at UCLA and a senior fellow at the Hoover Institution.