In the context of Liberator performance, bandwidth is the update rate delivered to all subscribed clients in bytes/sec.

Each test gives the details of the bandwidth used per client (look in the Test Details at the entry labeled "Bytes/second delivered to each client:"). For each test you can use this figure, together with the maximum number of clients that the Liberator was able to handle in the test (shown on the X-axis of the graph where the "elbow" occurs in the plot), to calculate the maximum bandwidth used by the Liberator for that test: bandwidth = update rate/client x maximum number of clients.