The click-fraud rate is around 14 percent, on average, less than the oft-suggested 20-35 percent, according to a new report from Click Forensics, which released its first Click Fraud Index in March, reports TechWeb.com. The monitoring firm said more than 90 percent of click fraud originated within the United States and Canada.

The average click-fraud rate across search-advertising industries is 13.7 percent, according to Click Forensics. It also reported that click fraud was far less on tier-one search providers such as Yahoo and Google - 12.1 percent - than on tier-two or tier-three providers: 21.3 percent and 29.8 percent, respectively.

The average cost per search term in the first quarter was $4.75 for the top key terms across the five biggest search-advertising industries: retail, financial services, health and fitness, technology and entertainment, Click Forensics said.

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