I'm fairly certain that a country with more than 2.6 million people on the internet [1] will use more than 256 GiB in a day... Even if just 256,000 of those people (~10%) downloaded a single megabyte in a day, you're already at the 2 terabit figure - and something tells me that much more than 10% of the internet connected population in NZ will download more than a single megabyte in a day.
Come to think of it, I probably downloaded around a megabyte worth of stuff just opening the article to begin with.
[1] Ministry of Social Development, New Zealand, "Telephone and internet access in the home." http://socialreport.msd.govt.nz/social-connectedness/telepho...