I'll add that it's worth including a kind of scale factor for what you expect your efficiency will be on your next leg of travel.
If you aim into a headwind at highway speeds, or are about to ride in the rain or cold, you'll get probably 80 miles of range, so scale the charging-mph numbers by 80%. Scale down further a bit if these factors all apply at once. I mean it, I've gotten a 50% range figure at 40F in a downpour with a headwind.
If you're in a bind and only one short trip leg from home or a hotel where you can finish charging, if you can get there at 45mph you'll probably get 120 miles of range, so scale the charging-mph numbers by 120%. If 25mph or so is okay, consider it 150% or more. This matters because it takes less time to do this than to keep charging so you can ride faster - you'll arrive sooner if you charge a bit less and ride slower.
Just to put this into context, I learned to do this on the 2013 DS which only offered 11 bars of charge indication, so I had to get an idea of how much range each bar represented, but quickly learned that varied by 2x or more depending on the factors above.