My 2013 Tesla P85 (6,500 miles) now has a range of 204 miles at about 85% charge - the loaner I just had (also a P85) had a range of about 220 at 85%, yet it has 2,000+ more miles than my car and it was newer. I thought lithium ion degradation was related to how many times the cells were charged / discharged, not their age? The loaner has clearly been charged/discharged more. So my question to you is this: what's your range at 85-90% (or even 100%) and hold old is your Model S? ps will report back when I charge my car to 100% tonight, but based on my calculations, my car should only have 240 miles max range; it was over 260 when it was brand new.