June 2017 post FRED traffic drops
In many online markets, May and June are typically slow months as weather improves and people spend more time outside than online. May 2017 was particularly tough on many sites due to the recent Google algorithm code named FRED.
From evidence coming in from around the webmaster community, FRED targets ad heavy, low quality sites.
This is rather ironic since the Google SERP's have in recent years becoming ad heavy themselves. Results in many cases seem poorly targeted, favoring big name sites posting thin, non authoritative content in an obvious attempt to simply churn more ads.
If the FRED update has rolled over your site, you can take some cautious steps to clean up your content. I say cautious because we never really know what these updates are targeting. There is a great article about what you can do about the FRED algo update over on FatJOe.co