More than half of the 4 million people missed in the 1990 census were children, and the Census Bureau's job of achieving an accurate count of the nation's youngest residents has only grown more difficult since then, according to a report released yesterday.

The children who were missed in 1990--like the adults who were not counted--were likely to be minorities, poor and living in big cities. Nationally, the 1990 census missed 1.6 percent of the total population, but 3.2 percent of those younger than 18.

Some children were overlooked because they lived in foster homes and their temporary caregivers mistakenly did not list them on census forms. Others lived in apartments where the lease did not allow children, and their guardians feared eviction if they listed them. Some were children of immigrants who were worried they would be deported.

An undercount of children has enormous practical consequences. Census data help determine the allocation of billions of dollars in federal funding for education, social services and other needs. The numbers also help government and nonprofit agencies decide where to locate day-care centers, health clinics and other services.

The problem of counting children has worsened since 1990, said demographer William P. O'Hare of the Annie E. Casey Foundation, which sponsored his report. The undercounted groups are growing, and the percentage of all households that return census forms has shrunk each decade, requiring more follow-up.

"The census is going to have to do a better job in 2000 just to stay in place," O'Hare told a news conference sponsored by the Census 2000 Initiative, a consortium of nonprofit groups concerned about reducing the undercount.

O'Hare and other organizations represented at the news conference--the National Association of Counties and the National Education Association--said they hope their focus on children who were not counted will win more public enthusiasm for an accurate count in 2000. Census day is April 1.

"Communities will pay more attention if they realize children are the ones who are suffering because of this," O'Hare said.

O'Hare credited the Census Bureau for its "Census in Schools" curriculum program and for targeting ads toward people with children. He said schools and employers should urge parents and workers to fill out census forms next spring and should assure people that their personal census information is, by law, confidential.

Regionally, undercounts of children were larger in the South and West than in the Northeast and Midwest. Among states, California and Texas had the largest numbers of missed children, 344,290 and 228,360, respectively, according to O'Hare's analysis of census estimates. More than 4 percent of children in those states were missed.

In Virginia, 65,958 children, or 4.2 percent, were not counted, and in Maryland, 52,139 children, or 4.3 percent, were missed.

The highest undercount rates were in big cities, topped by Oakland, Calif., where 8.6 percent of the children were left out. The census missed 7,901 children living in Washington, or 6.3 percent, according to O'Hare.

The Clinton administration and Republicans in Congress have been feuding over how to make up for the overall undercount. The White House wants to use a statistical sample to compensate for missing people, and Republicans insist on a direct head count. In January, the Supreme Court blocked the use of sampling to allocate seats in the House of Representatives but said it could be used for other purposes.

Uncounted Children

Cities with the highest rates of children missed in the 1990 census, according to the Annie E. Casey Foundation.

Percentage Number

missed missed

Oakland, Calif. 8.6 8,717

Miami 7.2 6,439

Hialeah, Fla. 6.4 2,980

New Orleans 6.3 9,103

Washington 6.3 7,901

Atlanta 6.3 6,357

Houston 6.1 28,554

Norfolk 6.1 3,913

Richmond 6.1 2,719

Baltimore 6.0 11,492

Dallas 5.9 15,871