There are several tracking tools that measure the traffic coming to your website and that can identify what search engines and what keywords have brought that traffic. Moreover tracking tools can also tell you what the visitor has done online, including page visits, time spent, actions taken (relevant for e-commerce sites or query/contact forms) and so on. You will have to find your survey methodologies to relate the traffic history to the revenue results. Some of these are mentioned below:

Doubleclick’s DARTDoubleclick’s DART paid placement and advertising ROI tracking tool generates web-based reports on cost per click, number of clicks, overall media cost, conversion rates, gross sales, return on investment (ROI), and net profit. Such tools are suited to online merchant sites.

WebTrends from NetlQOffers server-based software to determine how many visitors are coming to the Web site, where they’re coming from, what they’re doing on the Web site, and which search engines are sending the most traffic, along with which phrases drive the most traffic from each search engine.

HitBox from WebSideStoryIt uses a different data collection method, by enabling site owners to add code to their site. It tracks the same type of information that the WebTrends product does.

UrchinThis is another useful measuring and tracking tool.

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