Over the past five years, online ad revenues in Canada have more than quadrupled, according to a report released this morning by the Interactive Advertising Bureau of Canada.

Reported online ad revenues in 2008 were $1.6 billion, compared to 2004’s $364 million. The recent numbers also represent a leap of 29% over revenue for 2007 and respondents to IAB Canada’s survey projected those numbers will continue to grow.

“It’s pretty easy to measure your return on investment for online ads,” said Paula Gignac, president of IAB Canada. “You know the exact reach, exact frequency, you know that everyone sees your ad on their computers – it’s not like TV or radio where they could be out of the room. So online is accountable.”

Internet advertising in Canada now represents 11% of the estimated $14.6 billion total spent on advertising in 2008, trailing behind TV ads (23.2%) and newspaper ads (17.1%) and bumping radio ads down to fourth place (10.6%).

“TV, radio and newspapers have been delivering tremendous reach, and now we have almost 25 million people online in Canada, so you can really get reach there,” she said. “Also, what advertisers like to do is target, and online you can target an audience by region, behaviour or subject, so targeting becomes very pronounced.”

The report also noted what types of ads were leading the pack, revealing the following breakdown:

• Search advertising: $602 million
• Display advertising: $490 million
• Classifieds: $480 million
• Online video advertising: $12 million
• E-mail advertising: $18 million

Compared to the international market, Canada is just behind the U.S., where online ad revenue represents 12.5% of the overall number. And if Canadian trends continue, revenue is expected to grow to $1.75 billion this year.