San Francisco has the lowest percentage of children among its residents of any Bay Area county.

San Francisco had the lowest share in 2010, too, though that share jumped 1.7 percent over the next eight years, according to estimates by, a program of the Lucile Packard Foundation for Children’s Health and the California Department of Finance.

In all other Bay Area counties during that period the percentage of children in the population decreased.

Here’s how the percentage of children ranked by county in 2018.1. Solano — 23%2. Santa Clara — 22.9% 3. Contra Costa — 21.9%4. Alameda — 21.2%5. San Mateo — 21.1%6. Napa — 20.7%7. Marin — 19.8%8. Sonoma — 19.5%9. San Francisco — 15%[bar color=”Accent-Color” title=”1. Solano” percent=”23″][bar color=”Extra-Color-1″ title=”2. Santa Clara” percent=”22.9″][bar color=”Accent-Color” title=”3. Contra Costa” percent=”21.9″][bar color=”Extra-Color-1″ title=”4. Alameda” percent=”21.2″][bar color=”Accent-Color” title=”5. San Mateo” percent=”21.1″][bar color=”Extra-Color-1″ title=”6. Napa” percent=”21.7″][bar color=”Accent-Color” title=”7. Marin” percent=”19.8″][bar color=”Extra-Color-1″ title=”8. Sonoma” percent=”19.5″][bar color=”Accent-Color” title=”9. San Francisco” percent=”15″]San Francisco was the only county where the estimated share of children increased over the 2010-18 period, when it rose from 13.3 percent to 15 percent in 2018.

Lori Turk-Bicakci, senior manager for data and research at Kidsdata, said logistics are one possible reason for the lower share of children in San Francisco.  

“It’s just logistically more difficult,” Turk-Bicakci said, to get around on public transit with a baby and stroller and couples may think about this.

She also said the data show that the birth rate is the lowest in San Francisco, so the choice to start a family in the city may be made even earlier.; California Department of Finance,