Towards the end of last year, I was working on improving the search engine rankings for a small e-commerce site I own which sells personal security items like streetwise stun guns, the TASER X26C, and other civilian TASERS. My objective was to make a few tweaks and hopefully improve some keyword rankings before the holiday shopping season kicked off. In early October, I ranked 6th for the keyword responsible for 20% of my site’s traffic. I awoke one morning to find that suddenly I was on the third page for the keyword, a precipitous and scary drop.
I did some checking for other people who suffered a sudden drop in search ranking and got a variety of opinions. One blog post I found speculated that sudden drops could occur if Google penalizes your website for having duplicate content. This stuck out because the product featured on the page in question was sold on numerous other websites.
I headed over to Copyscape, entered the URL of my page, and found that it shared as much as 25% of its copy with more than a dozen other websites. I then reworded the copy and regained my ranking within about 3 days.
Algorithm changes can also cause your rankings to suddenly drop or spike. But if yours suddenly drops and you don’t hear anything about an algorithm change, you may want to check for duplicate content issues.