My iPhone 8 stayed at 100% after using it every day for 365 days. So no, your experience nor OPs experience is normal.Your iPhone's battery is expected to retain 80% of its charging capacity after 500 cycles. You should replace it by the time you reach it. In your case, 61 charging cycles is 12.2% of 500. I would say it's normal. My iPhone 8 Plus went down to 98% in just two months.