I am building a predictive model for the growth of the amount of users of a new p2p protocol inspired by bitcoin and I would like to use historical data collected from the growth of major social networks in my model. My specific questions are the following:Does a public database exist containing growth data for major social networks?Does there exist a generally accepted method for estimating contagion given specific network characteristics/assumptions?I need to account for the loss of users over time and thus I need a proper way of measuring node death and its impact upon connected nodes in the model. Is there a generally accepted method to estimate this given some set of parameters?As a side note, I am uncertain, which stack exchange to post this question in or the best way to format the question for this channel. If there is a forum one could recommend in the comments that is better suited, then I would appreciate the advice. 
Predicting the growth of a social network
graph theory;graph algorithms;social sciences