Reason behind keyword position down.

1. Manual or Algorithmic Penalty Rank Drop

2. You Got Out Ranked by a Competitor

3. Your Site was Demoted due to On-page Issues

4. Your Site Dropped Because it is Losing Links

5. Google Just Updated Their Algorithm

6. Google Flux

7. You’re Behaving in a Spammy Way

8. You Have Too Many Advertisements and less content, that increase the Bounce rate as well

9. You Have Duplicate Content

10. Another Website Launched Better Content