San Francisco Chronicle - (Sunday)
What age spread reveals about 15 Bay Area cities
looked at how ages are distributed across the 15 most populous cities in the Bay Area. We then visualized the age distribution of each city in one colorful chart.
According to the latest estimates, Fairfield has the largest share of young children among all 15 cities we examined. Just over 14% of Fairfield’s population is under 10 years old, and almost a third of its population is under 20.
This makes sense, as from 2010 to 2020, Fairfield had the highest growth rate of any of the 15 cities on our list. It grew by almost 14% over the decade.
Cities with younger versus older populations also have to adjust their spending priorities in sharply different ways. Young, growing cities have to invest more in schools, for instance, while places with aging populations may have to close schools and shift funding to senior services.
The town with the greatest share of elderly people is Daly City, where 12% of the population is 70 or above. Daly City grew by less than 4% from 2010 to 2020, ranking second-slowest of the 15 cities for growth and below California’s overall growth rate of 6.1%.
By comparison, Berkeley is remarkably youthful, with nearly half of its population ages 29 or below. The East Bay city has by far the largest share of people ages 20 to 29, and is tied for highest share of kids ages 10 to 19. There’s an easy explanation, of course: Berkeley is a college town, with lots of people in their late teens and early to mid-20s.
We also looked at each city’s median age according to the ACS. The medians all fell within the 30s, and most hovered around California’s overall median age of 36.5.
Again, Daly City ranks as the oldest and Berkeley is the youngest among the 15 we tracked, with median ages of nearly 40 and just over 31, respectively. San Francisco’s relative paucity of young children and teenagers tips it to the older side, but its big cohort of young professionals — it’s got the second-highest share of 30-somethings and the third-highest share of 20-somethings — keeps it closer to the middle of the pack than other retiree-heavy communities such as Concord and Santa Rosa.