  We investigate adblocking filters and the extent to which websites and
advertisers react when their content is impacted by these filters. We collected
data daily from the Alexa Top-5000 web sites for 120 days, and from specific
sites that newly appeared in filter lists for 140 days. By evaluating how long
a filter rule triggers on a website, we can gauge how long it remains
effective. We matched websites with both a regular adblocking filter list
(EasyList) and with a specialized filter list that targets anti-adblocking
logic (Nano Defender).
  From our data, we observe that the effectiveness of the EasyList adblocking
filter decays a modest 0.13\% per day, and after around 80 days seems to
stabilize. We found no evidence for any significant decay in effectiveness of
the more specialized, but less widely used, anti-adblocking removal filters.

Cryptography and Security;Networking and Internet Architecture