The answer is in the question:
"Your battery is currently supporting normal peak performance".
Don't worry; its in perfect condition.
And if you're anxious about battery health; then try The 40% to 80% rule:
To summarize; don't recharge the battery over 80% and never let it drop below 40%. And do a charge/discharge cycle once a month for recalibration.
I've been following that rule with my 3 year old Lumia and its current battery timing is more or less the same when the phone was brand new.