At what age are Pit Bulls fully grown?

As a keen observer of canine development, I'm curious to know at what point in their lives Pit Bulls reach their full physical maturity. Could you elaborate on the growth patterns and typical timeline for this breed? Do Pit Bulls, for instance, have a rapid growth spurt during puppyhood, followed by a slower but steady increase in size until they reach adulthood? Or is there a more gradual and consistent growth rate throughout their development? I'm particularly interested in understanding the age range when Pit Bulls are typically considered fully grown, as well as any notable physical changes that occur during this transition.