AdRoll also found that there was little overlap in audiences reached with FBX and web retargeting, indicating that advertisers should employ both to maximize their retargeting efforts.
AdRoll looked at 468 advertisers who ran campaigns on standard display and FBX in the last six months of 2012. On average, FBX offered 82 percent lower CPMs and 70 percent lower CPCs than web retargeting. However, cost per unique was 86 percent higher than elsewhere on the web, and clickthrough rates averaged 40 percent lower. Web display ads are much larger than Facebook ads, and they often include rich media, whereas Facebook ads are static and mostly text.
AdRoll found that only 8.3 percent of uniques — or 10.75 million out of 130 million — were reached by both FBX and web retargeting. This suggests that advertisers should be running campaigns through both in order to reach a more complete audience.
In a blog post on the topic, AdRoll wrote:
“Our research showed that both web retargeting and Facebook Exchange have their strengths and are incremental to one another. We found that by leveraging both platforms for retargeting campaigns, advertisers can maximize their return on investment. To do otherwise would be leaving money on the table!”