Triton Digital's September Internet Audio Top 20 ratings reflect some pretty significant growth for the aggregation of NPR Member Stations. The group has taken the #10 spot for Average Active Sessions (AAS) 6a-12M Monday-Sunday in the September Domestic Ranker (see chart below). The 12,236 AAS for NPR Member Stations is 58% higher than its August number. (While Triton's press release gives no indication, we'd guess it likely that at least some of this growth reflects the addition of more stations to this group.)
Religious/conservative broadcaster Salem Communications, #14 for the same ranker, saw its AAS rise 24% since last month.
The largest webcasters saw little to now growth month-to-month. Pandora's AAS was up 3%; CBS's continued to slide, down 11% since August (CBS online listening in this particular ranker is down 54% in the past 12 months. Compare that to Clear Channel, which is up 94% over the same time period).
Finally, something seems to have changed for Digitally Imported some time in August. Traditionally leader among Internet-only webcasters, DI dropped 57% in this ranker in the past month alone. It's likely a change like this reflects a measurement error of some sort. [UPDATE: Digitally Imported has indeed informed us that not all of its streams were counted in these most recent ratings periods. -- PM]
See all of Triton Digital's Internet Audio Top 20 Rankers here.