"I'd really like to see the source of the data and what exactly is being measured." Following the source link in Yglesias' post [1], the graph seems to come fr

"I'd really like to see the source of the data and what exactly is being measured." Following the source link in Yglesias' post [1], the graph seems to come from a presentation that Paul Heald (a professor at the University of Illinois) [2] did at the University of Canterbury [3]. A video is available on YouTube; the graph in question (with a different title) seems to be available at the 12:50 mark: http://www.youtube.com/watch?v=-DpfZcftI00#t12m50s http://www.youtube.com/watch?v=-DpfZcftI00#t12m50s [1]: http://offsettingbehaviour.blogspot.co.nz/2012/03/copyright-stagnation.html http://offsettingbehaviour.blogspot.co.nz/2012/03/copyright-... [2]: http://www.law.illinois.edu/faculty/profile/PaulHeald http://www.law.illinois.edu/faculty/profile/PaulHeald [3]: http://www.econ.canterbury.ac.nz/research/seminar2012.shtml http://www.econ.canterbury.ac.nz/research/seminar2012.shtml