FREDERICK COUNTY, Md. - Frederick County, Va.'s Hispanic community more than quadrupled since 2000, and has the fastest-growing Hispanic population of any other county in the nation, according to a new report released Thursday.

Among the country's top 25 metropolitan counties with rapidly-growing Hispanic communities in the new century, seven are in Virginia - more than any other state - and one in Maryland, according to estimates by the Pew Hispanic Center, a Washington think tank.

Culpeper County landed second place, followed by Fauquier (6th), Spotsylvania (10th), Stafford (11th), Loudoun (13th) and Prince William (23rd) counties.

Frederick County, Md. had the 15th fastest-growing Hispanic population on the list.

Many of the high-growth counties were typically outer suburbs or small or mid-sized cities, the Pew report said.

Richard Fry, Pew's senior research associate and the study's author, suggested that jobs were the driving force behind the population increases. The report does not address reasons for growth.

"Hispanics are sensitive to labor market opportunities. They tend to migrate where the jobs are," said Fry, adding that the Washington region's market has been robust compared to other areas. "I think that's probably reflective of why so many Virginia counties are on the list."

Additional factors such as cost of living, quality of life and a network of other Hispanics also has traditionally driven movement to outside of major cities, said Michael Fix, senior vice president of Washington's Migration Policy Institute, an independent think tank.

Top 25 counties with the largest Hispanic population growth from 2000 to 20071. Frederick County, Va. 2. Culpeper County, Va. 3. Paulding County, Ga. 4. Kendall County, Ill. 5. Henry County, Ga. 6. Fauquier County, Va. 7. Barrow County, Ga. 8. Luzerne County, Pa. 9. Newton County, Ga. 10. Spotsylvania County, Va. 11. Stafford County, Va. 12. Wapello County, Iowa 13. Loudoun County (web|news), Va. 14. Flagler County, Fla. 15. Frederick County, Md. 16. Douglas County, Ga. 17. Berkeley County, W.Va. 18. Lake County, Fla. 19. Robertson County, Tenn. 20. Hamilton County, Ind. 21. Delaware County, Ohio 22. Jefferson County, W. Va. 23. Prince William County (web|news), Va. 24. St. Lucie County, Fla. 25. Lancaster County, S.C.

He called such suburbanization one of the "massive trends" of immigration.

Chuck DeHaven, a member of the Frederick County Board of Supervisors, said his community nestled in the northern end of Virginia's Shenandoah Valley is indeed growing.

According to the census, the county's population totaled about 71,000 in 2006. But DeHaven was surprised to hear of the Pew report's findings.

"I haven't noticed," he said of the Hispanic growth Pew reports.

Nationally, Hispanics are the country's largest minority group, and since the start of this decade accounted for more than half of the overall population growth, according to Pew. The study found that from 2000 to 2007, their numbers mushroomed by 10.2 million to 45.5 million, or a rate of 29 percent. Unlike in the 1990s, Hispanics' growth was not due to new migration, but births.

Pew used census population estimates to identify 676 fast-growing Hispanic counties among the nation's 3,141 counties. The booming areas had a Hispanic population of at least 1,000, and a Hispanic growth rate of at least 41 percent from 2000 to 2007.

According to the report, the non-Hispanic population also increased in those areas.

Other residents are "moving for the same reason" as Hispanics, Fix said, referring to job opportunities.

Along with typically being suburbs, fast-growing counties had more Hispanic men than women, slightly more foreign-born nationals and Hispanics who weren't U.S. citizens. Those characteristics differ to more established, slow-growing counties nationwide, according to the report.

About one-fifth lived in poverty and about one-third had trouble speaking English - characteristics the Pew study found to be similar to slow-growing counties.

Pew also identified 10 locations - including Virginia's Arlington County and the city of Alexandria (web|news) - in which the Hispanic population had decreased since 2000.

Fry attributed that drop to high housing prices.