How much do we pay?

How do we determine how much to pay out (and thus how much to charge)? We want to pay back whatever sales are lost due to the Internet, but that's very difficult to calculate. First, not all sales lost are the Internet's fault (sales could be dropping because nobody likes the music being put out, the price points, or some other reason). Second, not all Internet downloads are lost sales (many people download songs because it's easier/cheaper than buying).

It gets worse when the Internet becomes the dominant medium for downloading songs, since we have nothing to compare against.

Anyone have any ideas?

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Aaron Swartz: http://www.aaronsw.com/