The internet will be weaving its way around the world for decades, but will there be fewer new users in 2011 than there were in 2010?
The internet is already considered so important in Finland, Spain and Estonia that access is a legal right. And the list of online possibilities keeps on growing. In 2010, the launch of Apple's iPad and other touchscreen computers made surfing more fun and intuitive, while several smartphone operating systems, especially Google's Android, took off, extending the mobile net's reach.
Despite internet ubiquity in the developed world, right now just 20 percent of individuals in the developing world are online. That low penetration, combined with ever cheaper devices, the ability to access the internet via cellphone networks and increasing broadband reach, will ensure that the fraction of the global population that is online keeps rising - for decades.
But sheer number of users isn't the only interesting internet data point. Below, we use the rate of growth in internet access to make some intriguing near-term predictions about adoption.
Prediction: Net slowdown
For some, the internet still feels pretty new. Indeed, the actual number of people online won't plateau for decades. But the net is still mature enough for the growth in adoption to begin slowing down soon.
Known as an inflection point, this milestone occurs in any adoption curve, when the number of new adopters starts growing a bit less each year rather than a bit more.
To find out if this might happen in 2011 for the internet, we plotted how the fraction of the world's online population has grown since 1990. It seemed to be consistent with a logistic curve, a pattern used to model myriad phenomena, from bacterial populations to tumour growth.
By assuming that the rate of increase in adoption continues to follow a logistic curve, we were able to estimate when adoption would hit 50 percent (see graph above). In a logistic curve, this always corresponds to the inflection point. Our calculation suggests we will reach this in 2013. So not 2011, but sooner than you might expect given that relatively few people are hooked up at present.
The estimate assumes that internet access will eventually reach 100 percent of the population. If instead, it plateaus at 80 percent, as it already seems to have done in the US, the world will reach the inflection point in 2012.
Samuel Arbesman and Rachel Courtland