In its inaugural Global Cloud Index (2010–2015), Cisco estimated global cloud computing traffic will grow 12-fold from 130 exabytes to reach a total of 1.6 zettabytes annually by 2015, a 66 percent compound annual growth rate. One zettabyte is equal to a sextillion bytes or a trillion gigabytes. To put that in perspective, 1.6 zettabytes is approximately equivalent to, 22 trillion hours of streaming music, 5 trillion hours of business Web conferencing with a webcam or 1.6 trillion hours of online high-definition (HD) video streaming.
