Nielsen: Many ads delivered outside advertiser targets

For instance, a laundry brand's ads may be targeted to Mom's between the ages of 25 and 35, but those ads may be delivered to Men at retirement age - and that discrepancy is impacting campaign ROI.

Although Nielsen reports overall ad growth of nearly 6% worldwide about half of the global markets saw a decline in ad spending. That decline makes it all the more important for ads to hit the right targets at the right time.

"Compared to the 8.9 percent growth rate in the first quarter of the year, there was definitely some slowdown," said Randall Beard, Global Head of Advertiser Solutions for Nielsen. "But, based on the global economy and the financial problems many countries have experienced, a 5.7% increase for quarterly year-on-year global ad spend is still great news."

For Q2 2011 the global ad spend reached more than $125 billion (USD).

Back to the Nielsen's study 33% of the ads for a beauty campaign reached the desired audience - women aged 18-34, but a startling 40% of those ads were delivered to men - an unintended demographic. Similar results were found in other campaigns. What's more, in that beauty campaign and others with high impression yields - 200 million and more - less than half of the impressions were delivered to the intended targets.

Still, Nielsen's report finds that online advertising is better at reaching specific demographics than some other ad mediums like television.

Tags: ad targeting, ad trends, NielsenWire, online advertising