CollEc provides rankings by co-authorship centrality for authors registered in the RePEc Author Service.
We have centrality rankings.
You can use the authors linked to by the rankings to find paths to any of the over 41,000 economists in the network. If you are in the network use a RAS handle to find yourself, and from you, find the path to anybody else in the network.
We don’t have current statistics. A count on 2018‒08‒15 found we have 1715265339 paths under management. Our computer constantly works to update them. With constant computing resources and a growing network, there is a growing gap between reality and the results. If the network would growing, then our calculation would converge to true values.
There is some documentation.