Demographic trends in San Diego County – new data from Census 2010

Population Growth 1910-2010
In the past 100 years, San Diego county has grown from a small city of 60,000 people to a thriving metropolitan area of more than 3 million. In San Diego’s early years Census figures show that the county’s population nearly doubled every ten years from 1910 to 1960. Between 1960 and 1990 growth slowed to an average increase of approximately 33 percent every decade. Growth slowed again in recent years, with less than a 15 percent increase 1990-2000 and only 10 percent growth from 2000-2010.

Migration Patterns
Migration was the primary driver of population growth at the beginning of the last century, but that trend has shifted considerably in recent decades. Until the late 1990s, most growth in Southern California was a result of in-migration from other parts of the United States and from other countries around the world.

However, according to data from the U.S. Census Bureau American Community Survey and a study by the University of Southern California Population Dynamics Research Group, that trend has shifted statewide, with most of the population now being, in the words of the study authors, “homegrown” (i.e. born in California).

Aging Population
As San Diego grows, it is growing older. The very first trickle in the aging wave of the Baby Boomers just turned 65 this past January. Because the Baby Boom is just now reaching this milestone, the proportion of the population age 65 and older had remained constant at 11 percent over the past two decades. However, that will shift dramatically in the next two decades.

On the younger end of the spectrum, the share of San Diego's population under the age of 18 is shrinking, from 26 percent in 2000 to 23 percent in 2010. As a result of these shifts the median age (the point at which half of the population is younger and half older) increased from 31.0 years in 1990 to 34.6 today.

Race and Ethnicity
One of the biggest demographic shifts highlighted by the 2010 Census is confirmation that San Diego is now a “majority-minority” county. This means that no single race or ethnic group accounts for more than half of the region’s population.

The Asian population, which grew fastest, increased by 34 percent (to 328,000 residents) between 2000 and 2010. The Hispanic/Latino population increased by 32 percent over the decade, and now accounts for approximately one third of the county’s total population (991,000 residents).

Conversely, the non-Hispanic White, Black, and American Indian populations all declined slightly during the decade (by 3, 5, and 8 percent, respectively)

Housing - Occupancy and Household Size
While much talk about the Census revolves around the demographic characteristics of the population, the 2010 Census also provides valuable information about neighborhood housing characteristics including occupancy rates and average household size.

In 1950, the average household size in San Diego was more than 3.1 persons per household. This decreased steadily as birth rates and average family size fell during the 1960s and 1970s, so by 1980, the region hit a low of 2.6 persons per household. However, birth rates began to rise starting in the mid-1970s, and a similar upward trend can be seen in average household size.

San Diego's lowest residential vacancy rates, not surprisingly, were during the housing boom in the early 2000s, and have risen considerably – back to rates reminiscent of the 1970s and 1980s – in the past three years. Data from the 2010 Census shows a residential vacancy rate of 6.7 percent for San Diego county.

2010 and Beyond
The demographic characteristics of the San Diego county will continue to evolve over time. San Diego is transitioning from a history of high-volume in-migration, to a more “homegrown” population, and from a relatively "young" area to a metropolitan area with an aging population.


Source data:
U.S. Census Bureau, Census 2010, Redistricting Files
California Department of Finance, Demographic Research Unit