Revive

If you have been losing traffic due to content decay, Revive can help you gain back that traffic.
Revive is a free tool by Animalz that finds decaying content in your Google Analytics, then suggests posts that should be refreshed.

With Animalz years of experience and knowledge they have accumulated from helping B2B SaaS blogs grow, you can be rest assured that you can get your site revived with the results given to you.