Deteriorating battery health

I've had my 2019 MacBook Pro (with a Touch Bar) for almost 9 months. I'm extremely worried about the battery health as it jumped from a 98% full charge capacity (8 months at 141 cycles) to a 93% full charge capacity (9 months at 151 cycles). I try my best to be mindful of how I use my laptop--dim brightness, open 2 tabs at most, drain until 50% only, cooling with a fan, etc.

I don't understand why my MacBook is behaving this way. Is this a hardware defect? Should I have it serviced? Coconut battery says the battery is operating normally at a good condition, but still, 98% to 93% is still an alarmingly big jump.