LONDON: The cost of buying search ads linked to brand names on Google is increasing despite the fact that clickthrough rates from the search engine are falling, according to research by the Search Group of UK ad industry body The Institute of Practitioners in Advertising.

Using anonymised, aggregated data drawn from 17 UK-based agencies, the IPA's Search Group found that the cost-per-click rate for brand names on Google rose by 31.6% in May 2008 versus the year-ago period.

By contrast, this data revealed that over a period of 21 months from April 2007 to December 2008, the average clickthrough rate for these ads hosted on the search portal fell from 28.9% to 20.9%.

To view the charts issued by the IPA Search Group regarding this data, click here (registration required).

Data sourced from IPA; additional content by WARC staff