I posted some rough data in the 90% thread and the 90D thread, but felt it might be appropriate to pull another thread here when discussing range and degradation. It's starting to get colder here in the midwest, and my displayed range after charge (at 90% and 100%) has been dropping again, as it has for the past few years when the colder weather rolls in. I've also noticed it picks back up in the spring. So I put my database of information from my car to good use (it dates back to October '13, data corruption destroyed the DB prior to that date) and graphed my range for both 90% and 100% charge levels. Here are the two graphs. First, 90% (selection criteria - all points, API battery_level = 90): Next, 100% (selection criteria - all points, API battery_level = 100 (that's right, I am not afraid to range charge!): As I noted in the other threads, I have not done any correlation with temperature, distance from range charge / rebalance, or software updates. I did go back and look at the anomaly that occurred on late Feb, 2014, when the graph does a correction upward. After thinking about it - this was the date that my rev A battery pack was replaced with the refurbished rev D pack following the contactor failure. Note that this is not the same thing as the snowflake that "reserves" some range in ultra-cold temps - this is the car's interpretation of the range of the battery. Conclusions to reach here: range display is seasonal and as you enter winter months, you may not be experiencing the degradation that you think is appearing... it's likely that it comes back in spring.