If you haven't seen this yet, it is a treasure trove of data on where EVs, PHEVs, etc are registered in the State of California, by county, by brand and model. You can look up your county and see if you have fellow Karma owners. For example, in my county, Contra Costa, there is just one Fisker Karma registered (me) and one Karma Revero. Meanwhile, there are 4.690 Tesla Model 3 and 2,760 Model S and 1,166 Model X. Chevy Bolt and Volt are also very prevalent. Anyway, check it out:
https://www.energy.ca.gov/data-repor...ger-statistics
And of course, the EV data at the USA level is very robust at the Department of energy's website:
https://www.eia.gov/renewable/afv/us...#tabs_charts-6