In our most recent PPC Jargon post we touched on something called Impression Share – a metric you’ll find in Google AdWords. It’s one of the trickier phrases we’ve introduced in the jargon lists so far, which left us wanting to come back today and offer a more detailed explanation of what it’s all about.
What exactly is Impression Share?
The official definition of Impression Share is as follows:
Impression share (IS) is the number of impressions you’ve received divided by the estimated number of impressions you were eligible to receive. Eligibility is based on your current ads’ targeting settings, approval statuses, bids, and quality.
*Source: Google AdWords Help
There are actually numerous types of Impression Share you’ll want to become familiar with, but essentially they reflect the number of times your ads display for the auctions you enter. This metric is calculated against the number of impressions Google deems you to be eligible for.
What does Impression Share tell me is about my campaigns?
Impression Share is a popular metric used to assess the health of AdWords campaigns and entire accounts. Be careful though, because Impression Share can be a misleading metric and there’s more to it than simply chasing the highest percentage and hoping for the best.
Understanding the different types of Impression Share
Before we go any further, let’s take a quick look at the different types of Impression Share you’ll need to consider.
Search Impression Share: Reflects your impressions on the Search Network divided by the eligibility calculated by Google.
You can think of this as your share of voice against your PPC competitors – the higher your Impression Share, the more often your ads show.
Display Impression Share: Reflects your impressions on the Display Network divided by the eligibility calculated by Google.
This gives you precisely the same calculation for the Display Network, although different targeting options come into play (which we’ll come to shortly).
Search Lost IS (budget): The percentage of impressions on the Search Network lost due to insufficient budget.
When you run out of budget your ads can’t show, even when they’re eligible. This cuts your Impression Share.
Display Lost IS (budget): The percentage of impressions on the Display Network lost due to insufficient budget.
Search Lost IS (rank): The percentage of impressions lost on the Search Network due to insufficient Ad Rank.
If you miss out on an auction because of low Ad Rank then that’s another dent on your Impression Share and a chance missed to show your ad.
Display Lost IS (rank): The percentage of impressions lost on the Display Network due to insufficient Ad Rank.
Search Exact match IS: A separate Impression Share for exact match keywords on the Search Network only.
Exact match keywords should be highly specific and aimed at users with a high intent. The are typically the most valuable impressions for you, so you want as many of them as possible.
So right away the different types of Impression Share can point out issues where your budget or Ad Rank could be limiting your number of impressions. This can point you in the direction of creating more relevant ads, for example (to improve Quality Score), or increasing your daily budget (even if it means reducing your bids slightly).
Just be aware that some advertisers put too much emphasis on Impression Share. In fact, you can say the same for Quality Score, ad position, max CPC and any number of other metrics. But these metrics are very rarely the goal of a PPC strategy – that’s normally profitability – so don’t go chasing Impression Share at the expense of the bigger picture.
That’s all we have time for today and sadly we’ve only managed to cover the very basics. No need to worry though, because we’ll continue to delve further into Impression Share in future posts and you can always get in touch with us if you need advice in the meantime.