I have lost my rankings, Google has dropped
Some of the back links to your website have been devalued. Where do the majority of your website’s back links come from: reciprocal, link pages or directories? These are the easiest forms of link building and, as such, are considered low quality by Google and its devaluing of those links will cause your rankings to drop. How much they drop depends on how many of these types of links are included on your website.
The relevancy of directory/link pages on your website has a great impact on how much value is originally assessed and whether the link will ultimately be devalued. As more and more irrelevant links are added to directories or link pages within your website, your site’s rankings will appear to fluctuate or drop lower and lower. Directories and link pages that have only a few links that are directly related to the website’s niche are considered high quality links, hold the most authority and value and are not likely to be devalued. This is why it’s a good idea to keep an eye on your back link profile and where you get your links. Be selective and don’t get a link just because it’s easy because good links are not easy to get.
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References
http://forums.seochat.com/google-optimi ... 70590.html