*Coverage* in Paid Search Campaigns

Assuming you are keeping an eye on the usual suspects like cost per acquisition, CTRs, avg CPCs etc, **coverage** could be the single most important metric that you are missing out on. Most beginning search marketeers ( and a lot of professional agencies in India !) dont track this very important metric at all. Before diving on, one caveat - the discussion that follows, is mostly relevant to highly competitive keyword landscapes only.

Let's begin by defining "coverage" - its a metric that's applicable to each of the keywords you are targetting.

Coverage = (no of times your ad appears on your target keyword)/(total no of searches on your target keyword)

Usually coverage is expressed as a percentage, and a simple way of conceptualizing it is thus : think of coverage as the number of times your ad appeared if hundred users searched for the target keyword. If your ad appeared every single time when users search for that keyword - the coverage is 100%

Two questions arise at this point -
a) Since we dont know the total number of searches on the target keyword, how will we measure coverage?
b) Once we measure coverage, how do we use it?


Let' take the first question - a) To measure coverage, we need to simulate the situation by actively firing the query against the search engine you are monitoring, for the geography you are monitoring. Let's say you are trying to measure coverage for the keyword "home loans" - you could fire the keyword "home loans" against google in india 1000 times, check how many times your ad was shown up and arrive at a fairly accurate estimate of the coverage percentage of "home loans". You would, of course, want to use an automated solution to do this !


Lets say, you see that the coverage percentage of "home loans" in your campaign, is 15% in Google. What do you do next?

Well - a broad thumb rule to follow is this : Maximize your coverage !

A very important step, once you have calculated the coverage, is to plot a graph with coverage % on one axis, and average ad position on the other axis. Once you have plotted yourself on the chart, plot your competitors for this keyword on the chart.

And then, ANALYZE !

If you do this exercise, you may realize and understand one of the biggest things many people don't seem to understand about search marketing -

Bidding higher can get you into a higher position, but does not mean you will get a larger number of clicks

For example, lets say you are bidding 50 INR for "home loans" - your average rank for this is 1 - and your coverage is 15%. Your CTR is 1.5%

What this means possibly, is that a lot of other competitors are bidding for rank number 1 - and the impressions are getting distributed across all these competitors - which is why you have a low coverage.


What should you do if you see a situation like the example above
You should reduce your bids ! So that you get to a lower position where there is less competition. Lets say, you lower your bid to 25 INR - your average rank comes down to 3, and your coverage is 60%. Your CTR is 1.25% ( CTRs are usually lower in lower ad positions )

Under such a situation, since your coverage increase overcompensates for any drop in CTR, you are going to get a lot more clicks when you reduced your bid as compared to when your bid was higher !! And moreover, you are paying less for each visitor !!

Now - a practical point - we obviously cant do this analysis for each and every keyword. However, if you have grouped your keywords into logical keyword groups, you should be able to do this analysis on each of your keyword groups, and modify your strategy at the keyword group level. OR, you could use a bid management tool you build or buy, which takes into account coverage as a metric to do this for you.

To cut a long story short, just remember this - bidding higher does *not* mean more clicks !