Click Through Rate
If one hundred visitors turn up at a given page, how many of them click the call to action? That's your click through rate. Or, if 100 visitors see your page listed amongst the results at Google (a SERP), how many click through to your page? Or, if 100 people are lucky enough to see your advertisement at twitter, and only 3 of them click on it, then you have a click through rate of 3%. Pull your socks up, Sonny Jim.
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