Crazy pace of decreasing per GB cost of hard-disk data storage

At the year 2000, the cost of hard-disk storage was ~$20 per GB. A quick calculation gives that a TeraByte disk that we can purchase for ~$100 nowadays would cost ~$20,000 about 10 years ago. Isn't this mind blowing?
See http://www.alts.net/ns1625/winchest.html for the hard-drive prices by year.