Actually using Gamerankings.com and basing the lists of games off of those we have listed under Rare development in the VGchartz.com game database I came up with this:
N64 era: average 88.2%
360 era: average 82.4%
whether or not this is a huge drop is your opinion, I just wanted to see how the numbers you put out matched with what I could find for myself.
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