2017 FFE Normal battery degradation?

[vkdyer]

My range has dropped over the last couple months. Since my last full charge, I've driven 85.5 miles over 3 days with 8 trips. The battery shows 10% remaining (and only 5 miles). If I add up the kWh for the 8 trips, it comes to 18.5 kWh. The battery has a stated kWh of 33.5. So according to these numbers, I used 90% of the battery but only 18.5 kWh. The car will be 8 years old in April. Is this normal degradation or does it sound like something is wrong?