The US Conference of Mayors reported late last year that hunger and homelessness had risen sharply in major American cities. Over the previous year, requests for emergency food assistance climbed an average of 23 percent and requests for emergency shelter assistance rose an average of 13 percent in 27 cities surveyed.

Hunger and homelessness are key indicators of poverty, yet census figures have documented a decrease in poverty over four years for most demographic groups, including those in America's cities.

The reason for this dissonance between the reality in America's streets and official poverty data is the federal government's reliance on the concept of the poverty line, an outdated measure that distorts the true picture of indigence in our nation.

First developed in the early 1960s, the federal poverty line reflects economic and social realities completely different from those faced by families today. Drawn up in1963-64 by a Social Security Administration official on the basis of a 1955 household food consumption survey by the Agriculture Department, the poverty line assumed that the cost of food makes up one-third of a family's budget.

Over the last 40 years, the federal poverty level has been updated to reflect inflation, but not social and economic changes. For most families today, food constitutes less than a fifth of their budgets while higher costs of transportation, housing, health care and child care have created new burdens. Moreover, the poverty line was calculated on a "Leave It To Beaver" model - the two-parent family with one stay-at-home parent. But that model doesn't accurately describe contemporary families and is particularly off-base for low-income families, where single working parents are more common than they were during the 1960s.

In nearly two-thirds of two-parent families, both parents work. For them, there are costs associated with employment - costs such as transportation, child care and taxes - that the federal poverty threshold either underestimates or neglects entirely.

Despite all evidence to the contrary, the federal poverty level measurement also assumes that costs are the same across all of the lower 48 states (the federal poverty level is higher for Hawaii and Alaska).

Yet in almost any city, small town or suburb in America, an annual income of $18,100 - the 2002 poverty figure for a family of four - is nowhere near enough to cover housing, food, clothing, child care, transportation and taxes.

But if the poverty line is an increasingly irrelevant measure of economic well-being, the debate on welfare this fall will be skewed. It's time to accept that the poverty line is an anachronism and to adopt a new benchmark.

Diana Pearce, a research at the University of Washington, has studied its inadequacies. While director of the Women and Poverty Project at Wider Opportunities for Women (WOW), Ms. Pearce developed a "self-Sufficiency Standard," which establishes a level for family incomes that is both realistic and flexible enough to address changing costs over time and from place to place.

Unlike the federal poverty level, the Self-Sufficiency Standard identifies the income levels at which families can meet their most basic needs without public support. It varies geographically, reflecting costs in different cities and counties across the United States for families of various sizes.

For instance, in Cocke County, Tenn., the Self-Sufficiency Standard for a single parent with two children is $23,091. In Indianapolis, it is $29,388. For each family, this is a "no-frills" budget covering only the most basic needs, such as food, housing, clothing, child care, health care, transportation and taxes. The food budget, for example, does not include any restaurant or take-out food - not even a pizza or a Happy Meal.

A more realistic measure of poverty will give us a new way to assess the success of social programs - not just whether a family moves a dollar above an arbitrary threshold, but whether it is moving toward self-sufficiency.

In addition to changes in welfare, we should make greater investments in child care, job training and affordable housing to help families fill the gap between what they earn and what they need.

The welfare reforms of the 1990s haven't ended poverty in America, but they may have inadvertently pointed the way to a broader policy framework to address the needs of the poorest one-third of families .

Deepak Bhargava is executive director of the National Campaign for Jobs and Income Support, a welfare reform project at the Center for Community Change. Joan Kuriansky is executive director of Wider Opportunities for Women.