There is a nonprofit called
Measure of America, and they came out with a list of California subgeographic areas based on quality of life measures like health, education, income, general well being.
Anyhow, the average score for the US was 5.07 out of 10, and here are their scores for the Top Areas in California:
One Percent California consists of the two neighborhood clusters that score 9 or above out of 10 on the HD Index; these neighborhoods are home to just under one in every one hundred Californians
Neighborhood clusters that score between 7 and 8.99 on the Index are Elite Enclave California; 15 percent of Californians are part of this group.
California's 1%
Rank/ Score/ Location
1 9.26 Palo Alto-Los Altos-Mountain View
2 9.26 Cupertino-Saratoga-Los Gatos
California's Elite Enclaves
Rank/ Score/ Location
3 8.96 San Ramon-Danville-Alamo
4 8.96 Walnut Creek-Lafayette-Orinda-Moraga
5 8.61 Redondo Beach-Manhattan Beach-Hermosa Beach
6 8.49 Calabasas-Agoura Hills-Malibu-Westlake Village
7 8.49 San Diego(Northwest-Del Mar Mesa)
8 8.42 Newport Beach-Aliso Viejo-Laguna Hills
9 8.38 Rancho Santa Margarita
10 8.24 Los Angeles(Pacific Palisades)
11 8.24 Palos Verdes Peninsula
12 8.18 Sunnyvale-San Jose(North)
13 8.13 Oakland(Hills) & Piedmont
14 8.10 Irvine City
15 8.03 San Mateo(South)-Half Moon Bay
16 7.99 San Diego(Northwest/San Dieguito) & Encinitas
17 7.97 San Diego(Northeast/Rancho Bernardo) & Poway
18 7.90 San Rafael-Mill Valley-Sausalito
19 7.75 Fremont City
20 7.75 Redwood City-San Carlos-Belmont
21 7.73 Santa Monica City
22 7.70 San Jose(Southwest-Almaden Valley)
23 7.69 San Francisco(Inner Sunset-Castro)
24 7.69 Livermore, Pleasanton & Dublin
25 7.58 San Gabriel Valley Region(North)
26 7.57 Los Angeles(Southwest/Marina Del Rey & Westchester) & Culver City
27 7.51 San Francisco(Sunset District)
28 7.51 San Francisco(North Beach/Chinatown)
29 7.50 Concord(South)-Walnut Creek(East) & Clayton
30 7.48 Berkeley-Albany
31 7.47 San Jose(Northwest) & Santa Clara
32 7.39 San Francisco(Richmond District)
33 7.36 West Hollywood-Beverly Hills
34 7.34 Carlsbad City
35 7.29 Thousand Oaks City
36 7.25 San Jose(West Central) & Campbell
37 7.23 Los Angeles(West Central/Westwood/West LA)
38 7.21 Mission Viejo & Rancho Santa Margarita
39 7.07 Long Beach(East)
This is from 2015 by the way, but I doubt much has changed although an update would be nice.
https://measureofamerica.org/california2014-15/