Hi Kb,   Thank you for your question. I don't know if there's a direct (number) answer to your question. Forteo has been shown in various studies to increase the bone density and reduce the risk of fractures in men and women with osteoporosis, but I don't think the increase can be broken down into a month-by-month increase in bone growth. In one study, about 50% of women experienced a 9-10% increase in bone density over 19 months of treatment. In another study, postmenopausal women taking Forteo experienced an average 9.7% increase in bone density, compared with a 1.1% increase when taking placebo.  If you want more data, I can give it to you, but suffice to say there's a good deal of data supporting its use. I hope this answers your question!   Best of luck, Casey