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Hey people, I'm sure many of you applied changes to the URL structure of a client's or your own website before. So did I for obvious reason: The structure before was like www.domain.com/brand_page/_22-key-word-translatedkeyword.php (ranked 20). This was changed to www.domain.com/key-word.html. 
Edit: Also on-page it was optimized, but only taking out worthless links like "keyword-link to other page" and adding a relevant SEO text (also valuable for the user) Now, for the targeted short-tail keyword, the outcome was great - ranking increased by 17 landing the page on the first SERP. But: Before this page garnered a wide range of long-tail keyword traffic.To be exact: 2600 different keywords generated traffic for that page in a period of 1 month. Now the newly structured site (also on-page optimized) only receives traffic from around 100 keywords. You can imagine that the absolute amount of visits also dropped. So I'd like to know if you observed similar results. Another question that's coming up in this context: How regularly does Google refresh the keywords associated with a page? Like: Is this page really relevant for this one keyword we associated it with 5 years ago? Because it is clear, when I'm looking at the aforementioned 2600 KW in detail, most don't have anything to do with the site, i.e. are not mentioned at all. Still they generated valuable traffic though. All of this is really crucial to this project, because soon the whole website's supposed to be relaunched with optimized URL structure and of course everything else that's need SEO wise... I'd love to hear your experiences. Thanks!!