If you think you’re reading the news, be warned that this story — and any other on the web — will be barely read by anyone 36 hours after it was first posted. That’s the message from a team of statistical physicists who have analysed how people access information online.

Researchers at University of Notre Dame and in Hungary have calculated that the number of people who read news stories on the web decays with time in a power law, and not exponentially as commonly thought. Most news becomes old hat within a day and a half of being posted — a finding that could help website designers or people trying to understand how information gets transferred in biological cells and social networks.