I am a bit curious. Is there an average growth rate for BPs? I ask because while I know in the wild it is important for them to get big quick, but how quickly do they normally grow?

We got our Ball near the end of December. I do not have a weight from when we first got her, but she was just a hair under 18 inches. Now less than two months later she is right at 26 inches and 311 grams. Is an 8 inch gain in length normal? We will feed her either one medium rat, or two mice (depending on what is available) a week.