Cost would be nearly impossible to calculate, or I should say I won't be the one to do it. Because first they were free, then $99/2yr, followed by reduced prices and now coupons that make them free, $2.17, $etc. Maybe after putting all that into play you can definitely say that there could be a P* graphed... but would be terribly hard to do as there are hundreds of registrars charging their own fees as compared to the beginning. Then again, you would have to take in CPI (I.E. that first $99 registration is worth $153 in today's dollars), etc.
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