Lots and lots of babies.
They're the primary reason the Northern San Joaquin Valley's population has grown, not immigrants or Bay Area transplants.
More than twice as many people were born as died in Stanislaus, San Joaquin and Merced counties from 2000 to 2006, according to U.S. Census Bureau statistics released today.
About 141,000 babies were born, while fewer than 60,000residents died.
And far more people moved to the valley than left during those six years. There was a net increase of nearly 45,000 foreign immigrants, plus nearly 87,000 people who migrated from other parts of the United States.
As a result, the three counties' population grew by about 210,000 people in six years. More than 1.43 million people now live in the region.
Juan Medina and his family are part of the valley's demographic trend. The 29-year-old native of Mexico has worked in Livermore for a decade, but he moved to Ceres last year to buy a house. Nine months later, his son, Jesus, was born.
"All my family is here," said Medina, noting how much more affordable it is to raise a family in the valley than in the Bay Area.
Rosalee Holguin also has found Stanislaus County a great place to raise a family. The 24-year-old mother moved to Modesto from Fresno, and she gave birth to a boy — also named Jesus — three months ago.
"It's family. It's more affordable. Everything's close," said Holguin, explaining why she likes it here. She said she would recommend her younger siblings consider starting their families in Modesto.
The region is popular with many young families because it's more affordable and less congested than the Bay Area, said Colleen Stephansen, 36, who runs a day care center in Modesto.
"I just think it's a better place to grow up than in the Bay Area. I grew up in the Bay Area, and I don't miss it," said Stephansen, whose center has a waiting list for infants.
Bay Area residents have been migrating to the Northern San Joaquin Valley for decades, but their flow decreased significantly last year.
Census statistics show Stanislaus, San Joaquin and Merced counties had a net domestic migration loss of more than 3,000 people from July 1, 2005, to July 1, 2006. That means fewer Americans moved in than moved out of those counties during those 12 months.
But that loss doesn't jibe with population estimates compiled by California's Department of Finance. The state statistics, released in December, show a net domestic migration gain of about 4,000 people for the three counties during that time.
Linda Gage, the department's senior demographer, said she is confident the state estimates are more accurate than those from the Census Bureau.
Gage said the Census Bureau determines population based on tax return data, but the state uses data from tax returns and driver's licenses.
"We think the driver's license database may be including people who are not filing tax returns," she explained. "Two sources are better than one."
As a result, the Department of Finance's population estimates are higher for virtually every California county, compared with Census Bureau estimates.
In Stanislaus County, for instance, the difference was about 7,000 people in 2006.
Once a decade, the Census Bureau conducts the nation's official population count, which strives to tally every person rather than just estimate who lives where. Between census years, the state and national governments produce annual estimates.
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