The Matrix is a system that periodically assesses every known industry website and ranks them in terms of their determined effectiveness and known search authority. Starting last week, and continuing until further notice, the system will update every day. For those that use the system as part of any performance-based program, the results are periodically reviewed and certified by a colleague that worked with Google's Search Team.
We've temporarily removed the unregistered API endpoint that ranks aggregation groups. Most other endpoints remain after the latest update, and all remain if using a registered key.
From a broker perspective, the system simply shows what is necessary to return organic results.
