Durham, N.C. - The U.S. Census Bureau poverty statistics scheduled to be released Tuesday likely will underestimate the nation's poor by more than 10 million people, largely because the formula used to calculate it has not been updated since 1963, says a Duke University expert on poverty.

"Each August, we Americans tell ourselves a lie," says David Brady, assistant professor of sociology at Duke. "This entire episode is profoundly dishonest."

Twelve and a half percent of the U.S., or nearly 36 million people, are "officially poor." But better estimates put those numbers closer to 18 percent, or 48 million people, Brady said.

One reason for the discrepancy is the way the government sets the official poverty level. The current poverty level was set by statistician Molly Orshansky, who constructed the formula for the official measure in 1963. With data from 1955, Orshansky multiplied the Department of Agriculture's "low-cost food budget" by three, assuming food amounted to one-third of a family's expenses.

"She developed this poverty line purely for research, never intended it for policy and quickly repudiated it," Brady said.

Unfortunately, President Johnson's administration substituted the "economy food plan" which was about 25 percent lower, and made it the official measure, he said.

"They purposefully set the line low so they could 'win' the War on Poverty," Brady said.

The measure neglects taxes and government assistance, has been adjusted only for inflation and, as a result, ignores the enormous changes in families since 1955. The Census Bureau has pushed Congress to revise the official measure, but it has not been revised.

Part of the problem is that state-of-the-art measures embrace relative poverty; that is, they take into account a person's poverty based on the society in which they live, Brady said.

"Someone might say that the U.S. poor are rich compared to people in Africa, but they don't live in Africa," Brady said. "Poor U.S. citizens are poor in the contemporary U.S., relative to what it takes to make ends meet and participate as citizens in their communities."

Using relative measures, U.S. poverty is nearly twice as high as that of Canada and the U.K and about three times as high as that of many European countries. The U.S. is the richest country in the world, but has the most poverty of any industrialized democracy, he said.