In a conversation with a business colleague of mine who is with one of our healthcare client accounts, she mentioned that it’s also important to consider the branding aspects of online display advertising. The idea that people may not click through at that precise moment in time, but are favorably disposed to pay a visit later on.
This got me to looking for additional research into the matter. What I found from several advertising digital media marketing and data reporting companies – MediaMind (Eyeblaster) and comScore – confirms this impression.
An analysis by comScore of consumer clickthrough behavior covering ~140 online display ad campaigns found that only about 20% of the conversions came after clicking on a banner ad. The remaining 80% of conversions happened among those who had seen the ad but not clicked through at the time. Instead, they converted at a later date.
Other interesting points from comScore’s analysis include:
Online display ad campaigns yielded nearly 50% improvement in advertiser website visits as measured over a 30-day period.
Users who were exposed to the online advertising were ~38% more likely to conduct an advertiser-related “branded” keyword search in the subsequent 30-day period.
Users who were exposed to the online advertising were ~17% more likely to make a purchase at the advertiser’s retail store.
Similarly, MediaMind’s analysis of ~100 million conversions from thousands of online ad campaigns has found concurring results – namely, that only ~20% of conversions are the result of a clickthrough, while the vast majority of the conversions happen at some point after viewing the banner ad without clicking on it at that moment.
The takeaway from all this: It’s a mistake to consider online advertising clickthrough rates in a vacuum. Because at best, it’s only a partial measure of the effectiveness of an online ad program.
Nones Notes 
So true! My take away from all this…too many people are trying to put communication in a spreadsheet. Doing so causes them to lose sight of the big picture, and they will end up making the wrong decisions. Communication is an intangible product, and gut feeling and common sense should prevail. Statistics and numbers should merely help decision making, not dictate it.
Indeed. How can we be confident any clickthrough and subsequent conversion isn’t triggered at least in part by some other “offline” marketing message, particularly conversions recorded some time after a clickthrough. (It reminds me of the notion of comparative fault in the legal system.) How do we REALLY know how to assign credit unless one strips out all sales/conversions generated by companies who do NOTHING but online banner advertising? And how many companies can get away with that? Back in the days when I was running occasional full-page ads in the New York Times, my online campaign stats —banner and AdWord clickthrough rates and conversions — would light up like Christmas trees as well.