Delivering data on the return on investment (ROI), return on engagement or any other type of measurement for search-related projects can be complicated. The client may feel less than satisfactory results from the project if there isn’t first a mutual understanding of the value of a visitor, a click or a conversion from search traffic.
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Things to consider:
For each site, the value of a visitor and what that visitor does will be different. Analyze and determine the revenue per conversion acquired from search traffic or the lifetime value of a new customer.
For informational sites or non-e-Commerce sites, determine if the client can place value on an email sign up form, returning visitor metric, etc.
Ultimately, place a value on actions and levels of engagement with the website. Tracking, measuring and analyzing this data will give you and your client a greater understanding of the value of search strategies and the value of the website to visitors.