The Noise Bottleneck or How Noise Explodes Faster than Data

Data: 90% is noise, 9% is already known, 1% is new information.

"Assume further that for what you are observing, at a yearly frequency, the ratio of signal to noise is about one to one (half noise, half signal)—this means that about half the changes are real improvements or degradations, the other half come from randomness. This ratio is what you get from yearly observations. But if you look at the very same data on a daily basis, the composition would change to 95 percent noise, 5 percent signal. And if you observe data on an hourly basis, as people immersed in the news and market price variations do, the split becomes 99.5 percent noise to 0.5 percent signal." Antifragile page 126

Nassim N. Taleb on the signal to noise ratio (and why you shouldn't read the news)

The Noise Bottleneck: When More Information is Harmful