There was a major update to Google’s Search Ranking Algorithm in November 2016 and a large drop in rankings for many websites in December 2016.
If you have seen a drop in your website’s search rankings it is likely due to the latest Google update thought to be focused on Mobile Quality
MozCast detected a change to Google rankings in November and industry chatter suggests that there was a core ranking update and the Mobile-first Index is being tested. The fallout of the new Google algorithm seems to be that sites with low mobile quality are impacted. Mobile quality scores relate to mobile web content and inbound mobile traffic. Here are some related articles regarding the algorithm change and the negative impact on rankings:
http://www.gsqi.com/marketing-blog/google-algorithm-update-november-10-2016-mobile-first/
https://www.seroundtable.com/google-search-update-22988.html
http://www.gsqi.com/marketing-blog/november-30-2016-google-algorithm-update/
There is more to it than just search rankings….We want our clients to focus on metrics that impact business results like traffic and conversions (sales, lead generation, engagement) rather than focusing on ranking reports. I refer to this article when talking about how ranking reports can change from minute to minute and that your rankings are only part of the picture: