Bluebulb Projects' The Measure of Things presents:
140 is about 0.00000010 times the number of Users on Facebook
In other words, it's 0.00000009720 times the count of Users on Facebook, and the count of Users on Facebook is 10,300,000 times that amount.
(March, 2015 figures) (monthly active users)
Facebook had 1.44 billion active users for the month ending March, 2015. In August, 2014, Facebook began a process of removing 87 million accounts that it had found to be fake.