Rise of the Digital Information Age

In 2002, digital data storage surpassed non-digital for the first time. By 2007, 94 percent of all information on the planet was in digital form. These were among the conclusions of researchers at the University of Southern California who tried to quantify the amount of data in the world. Source: Researchers at the University of Southern California took four years -- 1986, 1993, 2000 and 2007 -- and extrapolated numbers from roughly 1,100 sources of information. Credit: Todd Lindeman and Brian Vastag/ The Washington Post http://www.washingtonpost.com/wp-dyn/content/graphic/2011/02/11/GR2011021100614.html

See the related article at the Washington Post:

Exabytes: Documenting the 'digital age' and huge growth in computing capacity