Energy "since last charge" vs "energy consumption"

I don't think the idle power losses are tracked. Before sleep mode the car used a lot of energy and I don't remember seeing huge figures in the display.

I have noticed the same thing for some time now (over several firmware releases). My commute is about 40 miles each way, and in the morning I always note that when the "Since Last Charge" screen shows exactly 30.0 miles, the Wh/mi number is always higher than the Wh/mi number on the graph set to show the average for the last 30 miles. I figured they should be exactly the same at the 30.0 mile point in the trip.

As far as the lifetime Wh/mi question: no, it does not account for charging or standby losses.

I think the watts/mile is calculated while driving and so the "vampire" drain and charging losses are not counted. But when measured from the wall, changing losses and vampire drain is included. I expect the wall, or in my book the real number, to be a good 15% higher than the driving watts/mile.

Indeed... there is often discrepancy between the two numbers... this begins with pulling out of the grage and the "Since Last Charge " number has spiked up to 600-1200+ wH/mi (reflecting various subsystem energy consumption as the car starts up), without a corresponding spike in the energy graph (which would be difficult, as that energy is consumed with 0 miles driven).

I typically find the two numbers do match pretty closely after 30 miles... particularly under ideal conditions (warm weather, mild driving habits, etc...).

I tried to get a handle on some of the various display reporting a bit back... and there was some good discussion. Some behavior has changed with newer firmware, but it might be good reading if you are interested: Energy Accounting