My 2017 Ioniq EV with 62,000 miles on the odometer and 26 months of ownership is getting about 3.6 miles/kWh. I am seeing definite battery degradation after about 50,000 miles. It's hard to get more than 100 miles on a full charge now. I live on the coast of Southern California where ambient temperature doesn't fluctuate much. My driving routine has not changed and I used to get about 125 miles per charge when it was new, the variables that would affect individual rates are pretty much constant so I think it's battery degradation.