Blood python weight increase quesiton

So I was wondering how much my blood python should be growing per month. I read that a 30% increase in weight per month is average. Is this true?

While I have no experience with blood pythons, as a science project a few years ago my daughter tracked the feeder weights and snake weights of some of our young (under a year old) boas, ball pythons, and retics. Overall they converted 30-40% of the total "feeder weight" they received into body weight/growth.

YMMV.