Marketers at the top 50 global brands have upped their social game in 2015, with more than 80% actively posting to Facebook, Twitter, Instagram, Google+, and LinkedIn. Last year, only Facebook and Twitter surpassed the 80% mark, whereas this year, only Pinterest claims less than 80% adoption among the studied top brands. This is according to Forrester’s 2015 social networking benchmark, which reviews how the top 50 global brands use social media.

But despite the fact that the average number of fans has skyrocketed (these brands now boast an average of 18 million fans on Facebook, compared to 8.8 million last year) and a small increase in the average number of posts per week, user interaction rates continue to fall. Last year, Instagram saw a 4.2% user interaction rate (followers who liked, commented on, or shared a post); this year, that’s fallen to 2.3% for the top 50 global brands studied. This engagement trend is true for the rest of the social networks, except Facebook, likely due to the rise in paid promoted posts.

Learn more about the research here.