At the same time, whites and blacks continue to exit Baltimore City in significant numbers.
About 103,000 people left the city during the 1990s, lowering the population to 632,681. That's down 14 percent from 736,014 in 1990.
Baltimore officials acknowledge that residents, white and black alike, are leaving for the relative safety, better schools and lower taxes in the suburbs.
But they insist there are also signs that the outbound tide might be slowing.
"Several of our neighborhoods have seen increases in housing demand and property values," said city Planning Director Charles C. Graves 3rd.
More white-collar professionals, empty-nesters and families are seeking out homes near the water and in the city's leafy older neighborhoods, he said.
"In Canton, Federal Hill, Guilford and Roland Park, properties are turning over within a week's time. So we're getting some indication of renewed interest in the city," Graves said.
"Our challenge is to provide a diverse housing product, such as single-family detached homes with front and back yards, and two-car garages - those kinds of amenities being offered out in the county."
A major part of the growth in suburban minority numbers in the 1990s has been foreign immigration, especially in the Washington area, said Mark Goldstein, an economist with the Maryland Department of Planning.
Foreign immigration fueled up to 70 percent of Montgomery County's growth and up to 50 percent of the growth in Prince George's County, Goldstein said.
Gary D. Hughes, executive director of the Foreign-Born Information and Referral Network in Columbia, said the area's robust economy will continue to attract minorities and immigrants.
But he said immigrants seeking language tutors often have to wait four or five months. There also is a shortage of low-income housing, adequate transportation and affordable health care in the affluent county.
The resulting stress often plays out in substance abuse and domestic violence.
He said the Baltimore suburbs need to provide more teachers and more resources to serve the growing number of students with limited English skills.
In Baltimore County public schools, minority enrollment rose to 36.4 percent last year. That has made the goal of correcting racial disparities in performance on standardized tests a high priority for the new superintendent, Joe A. Hairston.
The 1999 population estimates are based largely on statistics from the Internal Revenue Service and the U.S. Immigration and Naturalization Service.
They do not include numbers from the 2000 Census.
Overall, Maryland added 390,881 people during the 1990s, bringing the total in July 1999 to 5,171,634, up 8.2 percent.
Two-thirds of the increase in Maryland was among blacks, who added 258,160 to their numbers during the decade, an increase of 21.6 percent.
Whites now constitute 67.5 percent of the state's population, down from 71.7 percent in 1990, according to the Census Bureau.
The fastest-growing counties in Maryland were Calvert, up 43 percent since 1990, followed by Howard (29.8 percent); Frederick (27.1 percent) and Worcester (24.7 percent).
In addition to Baltimore City, Allegany in the far west and Dorchester County on the Eastern Shore also lost population.
Baltimore County added just 4.6 percent to its population, joining Garrett, Kent, Somerset and Wicomico as the only counties with growth rates less than the statewide average of 8.2 percent.
Easily the most dramatic changes have been in Baltimore City, which lost an average of 12,000 people a year during the 1990s.
The white population fell by almost a third, or more than 93,000 people. The black population also fell, by more than 9,700 people, or 2.2 percent.
The numbers contrast with the trend in Washington, where the city's white population has shown an increase in recent years, reversing years of declines.
By last year, Baltimore was 67 percent black, compared with 59 percent in 1990.
Blacks seem to be leaving Baltimore for the same reasons as whites.
"Taxes, education, maybe crime. Those are the reasons I've been hearing over the last four years," said the Rev. Dr. Frank M. Reed 3rd, pastor at Bethel AME Church in Baltimore.
He said fully half the urban church's 15,000 African-American members now live in Baltimore County.
Buying a home in the suburbs "is an opportunity to build an economic base for your family," he said. "They have played the American game and won."
The only group that saw an increase in Baltimore City during the 1990s was the Hispanic community, up by 900 people to 8,514.
Montgomery and Prince George's counties saw the state's biggest increases in minority populations, followed by Baltimore County, Anne Arundel, Howard and Harford.
Baltimore County's minority population grew by nearly 40 percent, compared with the 4.6 percent growth in the total population.
In Carroll County, minority numbers grew 63 percent, compared with the county's overall 23.6 percent increase.
In Howard County, where minority numbers swelled 73 percent, signs in both English and Spanish greet visitors to Running Brook Elementary School in Columbia.
A large Asian supermarket has replaced a Super Fresh Grocery Store in Ellicott City to serve the town's booming Korean and Vietnamese populations.
Staff writer Lisa Goldberg contributed to this article.