In 2015 AWS deployed almost enough server capacity every day to support Amazon in 2005

In 2015 AWS deployed almost enough server capacity every day to support Amazon in 2005. James Hamilton #reInvent pic.twitter.com/Ux1KTSaSXm

— AWS re:Invent (@AWSreInvent) November 30, 2016

Facebook stores 600 terra-bytes of data a day

"At Facebook, we have unique storage scalability challenges when it comes to our data warehouse. Our warehouse stores upwards of 300 PB of Hive data, with an incoming daily rate of about 600 TB. In the last year, the warehouse has seen a 3x growth in the amount of data stored. Given this growth trajectory, storage efficiency is and will continue to be a focus for our warehouse infrastructure."
Source:  Facebook Code blog, 10th April 2014

Dropbox users save more than a billion files a day

"To hear the founders tell it, the plan is refreshingly simple and easy to understand for a Silicon Valley striver. The more places Dropbox touches people, the more people will put stuff in their Dropboxes. And the more stuff you put in Dropbox, the more you come to rely on your pervasive data — the more likely you are to pay for more space. Dropbox doesn’t say how many of its 175 million users are paying customers, though the company does say those users add 1 billion files to the service every day. Some of those people will need more space."

Source:  Wired, 9th July 2013

Note - Dropbox themselves describe this as 'syncing files' 

Dropbox users upload a billion files every 48 hours

"Over 50 million people currently use Dropbox, and users are adding files at a rate of one billion every 48 hours. But it’s not just viral growth, word of mouth growth, smart branding, and effective marketing."

Source:  VentureBeat, 12th july 2012

200m files are saved on Dropbox every day

"Dropbox will announce a number of milestones on Monday morning, we’ve learned. The file backup and sharing service was founded in 2007 by Drew Houston and Arash Ferdowsi.
It was in one of the early Y Combinator classes, now has 25 million users and 200 million files are “saved” daily, and more than 1 million every five minutes.
That’s impressive growth from the 4 million users the company had a year ago (they had two million in late 2009). Dropbox enables people to sync files and media across platforms and devices, in order to have them available from any location. The service also allows people to easily and quickly share files with others. Dropbox provides users with 2 GB of space for free, and they can pay for more."

Source:  TechCrunch, 17th April 2011