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And if you wish real hard, it'll come true.

Taylor Nelson's steady income should make WPP less vulnerable to a downturn in ad spending if the U.S. and other big economies enter a recession, analysts say. Many research products, such as television ratings and retail market-share data, typically continue selling well even when advertising demand slackens. In addition, the research industry is growing fast in the developing world, and global companies often prefer to use a single research firm in hopes of getting comparable data on a range of countries.