UK online advertising revenues for the first half of this year grew by a massive 42 per cent over the same period in 2000 despite tailing off over the last three months, according to recent research by PricewaterhouseCoopers (PwC).

The study, which canvassed over 50 leading UK websites, found that internet advertising revenues amounted to £90m for the first half of 2001, up £26m for the same period last year. It was the only advertising sector to show double digit growth.

Danny Meadows-Klue, chief executive of the Interactive Advertising Bureau (IAB) UK, said the growth showed that online advertising is now fixed in the media schedules for brand campaigns, and that a range of new standards had made the industry an efficient marketing option.

"Effective targeting and the accountability of online advertising are further reasons why advertisers are continuing to move their spend into the sector," he said. "As budgets tighten, online advertising lets them plan with precision accuracy how to deliver and monitor campaigns and track return on investment."

Banners still represent the largest component of online advertising revenue, but other formats, such as tenancies, nested content and sponsorships, are featuring more and more, according to the IAB.

The second quarter of this year saw a 10 per cent drop in revenues, but was in line with other advertising trends, said Paul Pilkington, a senior manager at PwC.

"Historically, the online sector has enjoyed unprecedented growth every quarter. Now it reflects the wider trend of a contraction in the entire advertising economy," he explained.

Online advertising now accounts for more than one per cent of total UK advertising spend, and this year's growth contrasts with the US, which saw an eight per cent fall over the same period.