If you're going to publish something, make sure it's during a time when as many of your Fans are online as possible. Particularly if you don't post many times per day. secondly, now its more about engagement on facebook. the more engaged your fb fans are with your content, the higher your edge rank is and fb will likely increase your organic reach.
to improve engagement, make sure you like, comment on responses from your page fans. doing this will lead to better engagement from your fans and in turn facebook will reward your better organic reach