To amplify Tim's point: Wal-Mart says on their Corporate Fact Sheet ( http://walmartstores.com/download/2230.pdf ) that they employ 2.1 million people. So 2.5 petabytes per hour is more than a gigabyte per employee per hour. Seems doubtful.

Hi,

I'm curious for the transcript.

Enjoyed it immensely. The English teacher and IT person in me appreciated that Brooke correctly stayed with 'data are' throughout the show.

One error, however, was hearing that Wal-Mart is saving 2.5 petabytes per hour. They've got that much data in total, but not nearly that much per hour.

That's a huge amount of data. I ran an IT department for a small ($80 million a year) company for 30 years. I kept a record of everything for that time - every shipment; every day of earnings for every one of 400 employees; every check cut; every bit of production data.

30 years' worth of data. 2.5 petabytes is that much data - for every man, woman, and child in the United States - twice over.

I quite enjoyed your piece on data journalism. I fully relate to the point, made by one of your interviewees, that in order to accomplish anything you have to do as little as possible on a consistent basis. This is exactly how I've been able to finish two (going on four) books. When people ask me how I do it I tell them that I keep my expectations low. If I pen five pages a day, five days a week, I've written 300 pages in three months. You cannot say, "Today I'll write a book," but you can say, "Today I'll write five pages of a book." Furthermore, if you fail to reach five pages, it's not the end of the world -- whereas if you fail to write that book, or even to start it, it can feel like the walls are crumbling around you.