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Freek Dijkstra
I captured screenshots of the AMS-IX on 19 june 2004 (soccer match Czech republic - Netherlands) and on 14 june 2010 (soccer match Denmark - Netherlands). See http://imgur.com/a/IZ48k#1. In 2004 the game was in the evening, and there was a small but noticeable dip in the traffic, presumably because people were watching the game instead of browsing the web. In 2010, there was a small spike. Presumably because people were watching the soccer game at work (the match was during daytime). This is more or less confirmed by two graphs of the traffic between the SURFnet network and the Dutch public broadcasting organisation (NPO), which rose from about 4 Gb/s to 16 Gb/s during the match. Unfortunately, I can't full explain the graph: the peak only last 1.5 hours, while I presume the match lasted 2 hours including break.