Maintain existing content
The search engines love new content. Out of date content leaves users with a negative impression of your site, as it does not seem to be maintained regularly. That doesn’t mean you should be creating new content every week. However, it is recommended that you make regular monthly content updates. The new content doesn’t have to be long, it is more important that it appears regularly.
Since 2011, Google has implemented a change in the ranking algorithm with the Freshness Update. This means that newly published content can rank better than the old one after a certain period of time.