Sudden drop in keyword ranking
Many webmasters experience a sudden drop in their keyword ranking at some point. Here are some possible causes and solutions.
1) Your website was penalized by Google.
Solution:
You can submit a reconsideration request to Google.
2) Your website has been hacked.
Solution:
You need to fix the security hole and then request a re-indexing from Google.
3) You have changes in your website content or architecture.
Solution:
You need to tell Google about the changes by using Fetch as a Google tool.
4) Your website is not being indexed by Google.
Solution:
You can use Google Webmaster Tools to check whether your website is being indexed and to find out why it is not being indexed.
Conclusion
While it is unclear what is causing the sudden drop in keyword ranking, it is important to take action to try and correct it. One possible solution is to audit your website to ensure that it is properly optimized for search engines. You can also create new content to try and regain your lost ranking.