The Washington and Baltimore metro areas, along with Miami and three Texas cities, have the lowest share of residents on public assistance, according to statistics released Tuesday by the Census Bureau.

The figures do not necessarily show where economic need is the greatest. Instead, they reflect the different approaches that states have taken to welfare, particularly during the recession, when some states changed eligibility rules and lowered benefits to cope with budget shortfalls.

The census analysis looked at programs representing only a fraction of all public assistance. It included welfare payments made through General Assistance and the Temporary Assistance to Needy Families programs, for example. But it excluded several large benefit programs, such as Supplemental Security Income to the disabled and children and the Supplemental Nutrition Assistance Program, which replaced food stamps.

Among those welfare programs it did look at, the census found only a small increase in share since 2000, despite an uneven recovery from the crushing recession. In 2012, the census estimated that 3.3 million households — 2.9 percent — received public assistance. That was a modest rise from 2000, when 2.7 million households — 2.6 percent, got welfare.

On the low end of the scale, only six of the nation’s 25 largest metro areas registered less than 2 percent — Washington, Baltimore, Houston, Dallas, San Antonio and Miami.

Conversely, Philadelphia, Riverside, Calif., and Portland, Ore., were the only cities that showed more than 4 percent of their residents on welfare.

Most of the states with low rates of residents on welfare were in the South or the Midwest. The highest rates were on the West Coast and in the upper Northeast.

The differences are largely the result of a wide spread in eligibility rules, said Ken Jacobs, head of the Center for Labor Research and Education at the University of California, Berkeley.

Texas and Florida are among the states that set a low income threshold for eligibility, Jacobs said, so many working poor are effectively unable to get public assistance. California has a high income threshold, making more workers eligible.

But Jacobs said a rise in food stamp and Medicaid payments suggests many people are struggling during a decade when incomes have been stagnant or fallen for many Americans.

“Compared to prior to the recession, real wages have fallen at the median and at the bottom,” he said. “There’s lower labor force participation. That means more families are in economic condition where they need public assistance.”

The Washington region’s strong economy is likely the reason why a relatively small fraction of households get public assistance, Jacobs said.