Brief:

• Instagram has overtaken parent company Facebook's social network among top 50 brand profiles and audience size, per a quarterly report by Socialbakers that was shared with sister publication Mobile Marketer. The research also found that brand engagement on Instagram and Facebook dropped during the holiday season, possibly indicating that brands didn't understand what kinds of content were appealing to consumers.
• Ad spend on Instagram Stories, the app's feature for disappearing posts, rose 40% from a year earlier to reach 10% of Instagram's total ad spend at the end of Q4. Spending on Facebook Stories also grew, but to just 0.4% of total spend on the social network. Facebook's core News Feed still led with about 58% of total ad spend, per Socialbakers.
• About 70% of brand videos on Facebook were horizontal and tended to be longer than one minute, indicating that viewers were willing to rotate their phones to watch lengthier content. Vertical videos were more than twice as likely to be 30 seconds or less, making up 21% of the video count, compared with 9.4% that were longer than 30 seconds.

Insight:

Advertisers continue to boost their ad spending on Facebook's platforms, although Socialbakers' data confirms other reports showing the growing importance of Instagram in the mobile marketing mix. Instagram Stories is drawing the most interest from advertisers among the format. Facebook announced at CES last month that the number of advertisers who use stories on Facebook, Instagram or Messenger had doubled to 4 million from a year earlier. Socialbakers' data suggests that most of that activity is on Instagram Stories.

Instagram also drove higher engagement than Facebook did during the quarter, although engagement rates are falling across its platforms — possibly indicating ad fatigue. The total interactions among the top 50 brands on Instagram were about 20 times bigger than those on Facebook in Q4, even though those brands posted more content on Facebook. The finding points to how brands must focus on higher-quality content in smaller volumes to boost engagement.

Vertical video has become a booming format due to its easy smartphone viewing, although some viewers are willing to rotate their phone to watch longer-form video, Socialbakers' data indicates. Vertical videos perform better than horizontal videos on Facebook, where 70% of videos on brand pages are shot horizontally. Viewers completed vertical videos shorter than 30 seconds — the most popular length — 30% of the time, while they completed horizontal videos 22% of the time.

Most fans and followers of brand pages on Instagram and Facebook are women, who represented 56% of audience engagement with brands in Q4. In the prime marketing demographic of 25 to 34 years, women made up the biggest group of people who mentioned and interacted with brand pages, per Socialbakers. That finding indicates the importance of social media in connecting with women, who make or influence 85% of all purchase decisions in the U.S., per data cited by Chain Store Age.