The division, which includes the agencies Millward Brown, Research International and Added Value, is the third largest at WPP, ahead of public relations and public affairs.
The figures were released as part of a trading statement in which WPP, headed by chairman and CEO Sir Martin Sorrell, reported revenues of 拢1.35bn for the third quarter, a rise in 26% on the reported figure for the same period last year.
Sorrell is looking to expand WPP's market research business and has his eyes on the Aegis-owned Synovate.
Strong like-for-like growth over the first nine months of the year led WPP to raise guidance for 2005 revenue growth to between 4% and 5% from previous estimates of 3% to 4%.
WPP said that prospects for improvements in trading performance remain good. However, it warned were worries about the US economy.
"There are still concerns about the prospects for the US economy, focused on the twin deficits and on the indebted consumer and the impact of increasing interest rates and rising commodity prices, including oil, on inflation," Sorrell said.
All regions had performed well with the exception of Western Europe. In particular, growth levels for the UK lagged behind the average, at 9.7% for the quarter compared with 22.8% for the WPP as a whole.
Breaking the revenue down into services showed that advertising and media investment management had shown the strongest growth, up 30.8% for the quarter.
Public relations and public affairs revenues were up 16.5% and branding and identity and healthcare and other specialist communications rose by 26.6%.
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