What is First Time Impression Ratio? Here's Why it’s Crucial to Scaling Facebook Budgets

By: Tom Murray | Managing Director

Facebook has a bevy of tools for marketers to use to understand the performance of their campaign, and one of the most underutilized of those tools is the Ad Set Delivery Status “Inspect” tab. It doesn’t help its case by being buried as a button on the window pane menu - but to get there, you need to click on “edit” at the ad set level, and then click the magnifying glass. As a heads up, this is only valid for non-dynamic ads.

When you click into here, you start to see a much deeper level of analysis into how your ad set is faring in the auction. Most marketers just look at the front-end metrics such as CTR, CPC, CPA, and CPM, but going one step further allows you to really see what is going on under the hood.

As you scroll down, you may see a chart such as the below, which is focused on audience saturation. Audience saturation shows you some metrics around frequency, reach, and percentage of audience reached.

As you scale up your spend, you will naturally start hitting a higher percentage of the available audience or a higher frequency (meaning you are hitting people you’ve already reached again with ads). As you increase your frequency, this will decrease your “first time impression ratio,” which is the percentage of users on a given day that are seeing their first impression in that ad set. As campaigns go on, this tends to lower over time. In the above example, you can see the bold green line getting lower each day, and the blue line is rising at almost a directly correlated rate. The blue line is the CPA of the ad set, which is the crucial piece here. As the first time impression ratio goes up, CPA typically will go up over time.

This tends to happen with smaller audiences (1-2 Million people) because if there is a smaller pool of people to reach, the chance of reaching them again or reaching a higher percentage of them is much higher than going with a broad audience (say 10 Million people or more).

How can you combat a declining first time impression ratio?

1. Launch new audiences: Expanding audiences can help you find new people that aren’t currently being reached. In addition, Facebook has been preaching broader audience targeting for a few years now, recommending that you allow the pixel and the ad set optimization engine to over time find your best customers.
   
2. Launch new creative: Higher frequency isn’t necessarily a bad thing, but if you keep sending the same ads to people, then they are going to be less likely to interact with them. Sending out new ads will freshen up the content and allow you to test different angles to get your target audiences to eventually convert on your ads.
   
3. Test out new bid controls: When first time impression ratio declines, costs will typically go up. Using bid controls can help cap the costs that you see on your ads. It might lower delivery, but if cost control is your number one priority, these bid caps can help give you some cost ceiling.