Sorry to say the NAV data is..well outdated at best...
I would recommend downloading and installing the ChargePoint App, the Bliink App, and the WattStation App on your mobile phone.
They will each tell you the rates for their own charging stations...find the charging stations most prevalent in your area and sticking to that one app should make life easier then having to browse all 3.
Personal preference for Nor-cal is ChargePoint as I find more of them free than I do of Bliink, and GE WattStation...well it's still getting off the ground out here..long way to go..(trying to get them to hurry it along) .
Hope this helps...doesn't help you get much value out of the NAV though, sorry.
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