As an example of degradation and range of battery.... I drive the same way, every day, on surface streets, mostly blvds with a 40 to 45 mph speed limit. 26 miles round trip. Live in Los Angeles suburb.
When new, I would have the Guess -O -Meter showing 129 miles of range.
I've got a 4 year old battery now, effective exactly today, with 24.5k miles on my 2015 SEL. Guess-O-Meter now shows 113 to 115 miles on a full recharge.
You can get numbers like that if you have the skill and / or patience to drive like an old man. You'll get the 83 miles x about 0.88 if you drive a lot of miles in 4 years, and you drive the car harder than I do, which is almost everyone around here except a few others.
This is a BB where driving enthusiasts hang out, and they drive their cars harder and more abusively than most. So you have to take that into consideration too.
Driving an electric car, for some, like me, is about energy management. You don't really have a lot of energy stored in that 700 # battery. How you manage what little you have has a big effect on how far you can go before recharging. Much like a smartphone. Are you a gamer? A power user?, a Textoholic? Or do you just use it to make phone calls? Do you time out your lighted screen ASAP? All of those uses affect how long your battery lasts in a smart phone.