This is a 2 part question. The first question is about realistic growth rates:
What is a realistic growth rate of visitors for an online property such as a blog over a 12 month period? I'm guessing the range is anywhere from 0% to 10,000% for a new website, and around 10% - 500% for an established website.
The second question is about calculating a monthly growth rate:
500% or 10,000% would be a year-on-year statistic. But if you had to take into account (an assumed perfectly stable) compound growth, what would the monthly growth rate be? 10,000% divided by 12 = 833%? per month?