If you set up goals for your contact page, trial submission page, and other conversion starting points, this is a fairly valid KPI for just about any SEO campaign (assuming there is a simple pathway to goal pages from SEO landing pages). The purpose of SEO is to increase visibility of a website in search for target keywords, increase relevant organic visitor traffic, and connect the dots to facilitate a conversion. We start to enter a gray area when we begin looking at how visitors behave after they have arrived at goal pages, because this is largely impacted by website design, messaging and user experience.
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