Good stuff - it may take me awhile to read all of it.
What jumps out at me is the gaps in data. I know the Rand study from the 70s is a "classic" of sorts, and frequently quoted in other papers. I'd have thought that after 2001, a major study like this one would have been done for the obvious reasons. (Or maybe, like my co., they did an "in house" study and did not make it publicly available.)
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