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"...slowly going downwards over the year" This sounds like possibly user metric related, which are important ranking factors no tool is able to give us. It's possible, users have showed preference to other pages ranking for that query over time. Metrics could be; click through rate from SERPs bouncing back to SERPs ("pogo-sticking") time on page repeat visits to the page direct visits the page completed actions on that page ...etc Essentially, users might be telling Google they don't like the page based upon their behavior. Some suggestions; Watch Rand's video about how to improve Pogo Sticking Check out these articles on improving CTR in the SERPs (most the top ranked resources there are good) Set up goal tracking to get a conversion rate Try Justin Cutroni's scroll tracking to see how users are interacting with the content Try a heatmap program like http://www.crazyegg.com/ Without being able to see your page, it's tough to give custom recommendations, but I would also recommend making sure you have the best design of any site in your niche for your audience.