Apparently, the average of 76% is based on average Phoenix LEAF-driver milage of 7,500 miles per year. If 76% is an 'average' based on 7500 'average' annual milage, if you are driving over 7500 miles per year, you will end up with lower than 76% after 5 years in warm climates. [Correction: Phoenix, no estimates posted for other affected areas]

http://www.greencarreports.com/news/107 ... -exclusive" onclick="window.open(this.href);return false;

[UPDATE: After this article was published, Nissan used the actual mileage of the seven cars in the test to provide additional data. "The average mileage for the cars investigated was 19,600 miles, and the average in-service time was 14.7 months," wrote the company's Katherine Zachary. "Average annual mileage [of those cars] is about 16,000 per year, more than double the average Phoenix customer mileage of 7,500 miles per year."]

Also, I don't remember much about my stats classes, but mean is relatively meaningless without distribution, median, min, and max. Is averaging these numbers meaningful with a sample size of 7? Of the 4 cars I know about the spread is 12,000 to 24,000 annual milage.