Internet users are spending around half of their time online reading content and watching videos, more than that spent on e-commerce sites, search engines, and sending emails and messages.

The Internet Activity Index from the US Online Publisher’s Association looks at how users spend their time online, dividing it into four categories; content, communications, commerce, and search.

The OPA’s figures, provided by Nielsen//NetRatings, show that the percentage of time spent on content has increased by 37% over the past four years, and stood at 49.6% in June 2007.

The OPA attributed the growth in online content consumption to broadband, the popularity of online video sites and social networks, as well as the fact that there is now so much more content available online.

The share of time spent using search engines has also increased, from 3% in 2003, to 5% this year, while time spent on e-commerce sites has dropped by just 1%, from 16% in 2003 to 15% in 2007.

Time spent on communications has fallen more dramatically, from 46% four years ago, to 33% this year.

The OPA stats use Nielsen’s time spent metric, and measures sites that account for over 90% of web users and 55% of total online time.