Exonar have released a big data calculator to discover how much data you really have. By inputting an estimate of how much you have (in terabytes or gigabytes), you can discover metrics such as what word count your data equates to, and how far it would stretch if printed out laid end-to-end.
For instance, according to Wikibon, Walmart had access to over 2.5 petabytes (2,500,000 gigabytes) of data in 2012. This equates to 1.69 trillion pages stored in plain text, and 593.22 trillion words. It also adds to 48.1 miles of Word Documents printed out and laid end to end.
To reach the moon in printed Word Documents laid end-to-end, you end 55500 terabytes of data.
Explore the calculator for yourself here.