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Hi Max, It is difficult to comment without seeing your website. However, if you are constantly loosing rankings with every search engine update you could have low quality content or have grey/black hat link building techniques happening offsite. These types of techniques are short lived, the search engines smart, and will result in inconsistent rankings. BTW - I'm not implying you have a junk site. Address your content (there are plenty of good articles in the SEOMoz Blog here) and secure some quality links to ride out future algo changes. Hope that helps. Cheers, Andrew