Spikes often deserve special attention when analyzing your site. They can indicate interesting developments in your industry, marketing impact or press coverage. Here’re couple of examples of situations that might cause a spike:

1. The number of visits from a certain referrer, such as stumbleupon.com, suddenly jumps when a blog post gets attention
2. Your conversion rate falls to zero because of an error in your signup form
3. Your percentage of new visitors suddenly increases from an event sponsorship
4. Your bounce rate spikes due to a redirect error

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