The mobile share of search budget continued to steadily increase 1% per quarter in 2017, reaching 53% in fourth-quarter 2017 -- up from 49% in the year-ago quarter for Marin Software clients, according to data released Thursday.
The cost per click (CPC) for mobile campaigns rose 25%, compared with the year-ago quarter. Mobile CPCs still cost less relative to desktop CPCs, but the gap is closing quickly.
CPCs in the education industry remained the most expensive, with an average of $3.80. This represents a modest 2% decline from third-quarter 2017. Travel and Technology saw the lowest average CPCs of $0.49 and $0.50 -- and both saw quarterly decreases of 12% and 6% respectively, per the report. Retail hit about $0.70 and B2B Services about $1.75.
Overall, click volume throughout 2017 fell from fourth-quarter 2017 to third-quarter 2017 and then began to bounce back from the third quarter to the fourth quarter of 2017, although marketers spent more throughout the year.
The report also noted a 3% increase in creative-light ad groups during fourth-quarter 2017, which the company found surprising. In the third quarter of 2017, Marin noted that Google's improvements to its creative rotation technology rewards advertisers using three or more ads per ad group with increased clicks and impressions.
Shopping Ads fared well, with an 8% increase in clicks and 31% increase in click share, retail advertisers continue to find success. The report suggests an increase in use during 2018.
Social CPMs rose year-over-year, while click-through rates remained flat, which may indicate personalization is not keeping pace with consumer expectations, according to the report.