Health battery

Your battery is fine.

Batteries degrade over time with usage due to chemical aging, that's just how they work.

You can expect about a 1% drop per month with average use on an iPhone.

Apple recommends replacing it when it reaches 80%.

iPhone Battery Replacement.

iPhone Battery Repair & Replacement - Apple Support

About Lithium Ion Batteries

iPhone Battery and Performance - Apple Support (IN)

Here are some tips on maximizing battery life.

Batteries - Maximizing Performance - Apple

Battery Health is an inexact figure that varies with usage. The typical Apple Battery lasts about 2 years with normal use. When the battery Health reaches 80%, it will be time to make an appointment at the nearest Apple Store for Battery Replacement. Your Battery Health sounds about right for a 2 year old phone.

Yes, that's right! I have the same phone and my battery has about the same health as yours.