The March 2012 report notes that results for individual advertisers may vary, and that the study focused on clicks rather than conversions.
Increase in Search Ad Spend Drives Clicks
A February 2012 report from Google showed that on average, 85% of clicks were lost and not recovered by organic clicks when decreasing search ad spend to zero. The report noted that this was lower than the original 89% from the 2011 study because of additional advertisers included and also likely due to seasonality effects. When search ad spend was decreased, but not completely paused, on average 80% of clicks were lost and not recovered by organic clicks.
Conversely, increasing search ad spend from a non-zero base increased clicks by an average of 78%, while increasing search ad spend from a zero base drove an average of 79% in gained clicks.
Most Ads Occur Without Associated Organic Result
Meanwhile, Google’s March 2012 also found that search ads appear with no associated organic result on the first page an average of 81% of the time. In fact, a search ad shows up with an organic result in the top rank just 9% of the time, with an organic result in ranks 2-4 only 5% of the time, and in lower ranks on the first page roughly 4% of the time.
On average, 66% of ad clicks occurred without an associated organic result on the first page.