LONDON: Online advertising expenditure will continue to rise in Western Europe over the period to 2014, with the expansion of display set to outpace search by this date.

Forrester, the research firm, has released its latest forecast covering 17 countries in the region, a list that includes France, Germany, Italy, Spain and the UK.

According to the company's estimates, total display ad sales fell just short of €3bn ($3.8bn; £2.5bn) in 2009, up by 1% year-on-year, with search posting revenues of €6.6bn.

These figures are expected to stand at €3.1bn and €7.3bn in turn in 2010, as marketers exploit the high level of measurability provided by this medium during a time of economic uncertainty.

Further growth is likely to follow in 2011, when display returns are due to pass €3.3bn and search will reach €8.5bn, according to Forrester.

The internet should maintain this momentum in 2013, when display will be worth nearly €4bn and the value of search will increase to over €9bn.

By 2014, brand owners in Western Europe are pegged to invest more than €9.5bn in the paid-for listings offered by sites like Google and Yahoo, with display on €4.4bn.

Despite the fact search is set to remain dominant in financial terms, Nate Elliott, an analyst at Forrester, said greater opportunities for targeting and new formats may encourage clients to look elsewhere.

"We think the big story between now and 2014 will be online display advertising," he said.

"We're especially excited about the prospects for rich ad formats like pre-roll video ads and Flash-based creative."

In 2009, these types of ads generated more spending than "traditional online image ads" for the first time, and rich media formats are set to take a 63% share of all display outlay by 2014.

Marketers are also predicted to spend over €1bn on online video advertising in four years times, as more consumers and broadcasters take to this medium.

In contrast, Elliott suggested the "glory days are slowly coming to an end" for search as annual growth rates moderate, a trend that has been observable in each of the last six years.

"Unless there are remarkable developments in search technology – developments that, frankly, we don't see coming – by 2012 online display ad spending will be growing faster than search spending for the first time," he said.

Data sourced from Forrester; additional content by Warc staff