Search and Search

Why has Yahoo dropped my website from its search engine/directory results?

My website always ranked on page 1 of Yahoo in keyword searches and in some cases it was in the no. 2 spot. I also had a high ranking on Yahoo local. I just discovered that my website has been eliminated in the last week or two from both Yahoo search results and Yahoo local business listings. Why?
My website always ranked on the first page in Yahoo Search with the top keywords for my business. For the most popular keyword, I was no. 2. I also had a high ranking on Yahoo local. But, I recently discovered that sometime in the last week or two, my website ranking just did not drop, my website has been eliminated in Yahoo Search keyword queries and has been eliminated from Yahoo local business listings. My title, description and keyword meta tags all are appropriate to my business, are found in my web pages, and are like my top competitors. I have not keyword stuffed. So, why the major diss from Yahoo?

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