Moz just released this month their MozCast year in review infographic which does a really good job breaking down some of the most volatile days in search over the last two years. I highly recommend checking it out!
Before we proceed any further it’s important to give some background on exactly how MozCast tracks things and what “volatile” means in this context. MozCast tracks a set of 1,000 keywords every 24 hours and pulls the top 10 organic results. MozCast then compares those set of kewyords to the top 10 keywords from the previous day. The hotter the temperature on MozCast the larger the change in those rankings. The bigger the change the more volatile the algorithm is that day.
One thing that may surprise you is while some of the higher temperature days (70 degrees being the average) do correspond with confirmed updates there are plenty of days where there was clearly some sort of change occurring in the search algorithm but no confirmed update. As Gary Illyes points out frequently, as seen in this tweet below, Google makes hundreds of changes to their algorithm.
@AGr4ves Sorry, Alex, we don’t confirm updates to our core ranking algorithms. We make hundreds of changes to it, this could have been one.
— Gary Illyes (@methode) October 22, 2015
Getting back to the infographic, some of the things I took away from this informative infographic were:
- There appear to be a lot more confirmed updates in 2014 versus 2015.
- I was pretty surprised the most volatile day June 16th 2015 was not attributed to a confirmed update. In fact the year before the closest date that was as volatile was May 19, 2014 which was the Panda 4.0 update. As a refresher, this update hit low-quality content. Some of the so-called losers of this update included popular sites like Retailmenot.com and Ask.com.
So what was the June 16, 2015 update?
We may never know definitively but there were some good theories. Gary Illyes came out and dismissed the theories that this was a Penguin or Panda update. Moz’s Dr. Pete had a good theory that it might have something to do with HTTPS but Gary from Google also dismissed that theory. So what was it?
One interesting part of the Dr. Pete’s theory was that Wikipedia was during this same time frame switching their site over to HTTPS. Could one very large site trigger tons of search term movement? Personally, I believed this theory originally only because if you think about it a lot of Wikipedia content is pulled into top search positions as well as the knowledge graph. Since MozCast is focused on the top 10 organic results it seems completely likely that a site that shows up in the majority of top organic results could be catalyst for all of this. However, this theory wasn’t quite accurate either.
Searchmetrics‘ founder Marcus Tober came out with what I consider to be the leading and best supported theory. It appears that news sites specifically such as Time.com and Techcrunch.com came out with better rankings after June 16, 2015. See this chart below via Searchmetrics as evidence of the increase in search visibility for Techcruch.com
Interestingly enough, Google Trends had a relaunch on June 17th, one day after all of this activity in the search engine. It appears this update allowed Google to immediately update based on the trending topics. For instance if a certain news event broke and this led to more searchers typing a query into Google the search engine could immediately serve up the most relevant content, both new articles and old articles about that same topic.
Personally, I have to wonder if this update had something to do with when RankBrain started to take a larger part in Google’s algorithm.
I think the big takeaway here is that the algorithm is quite literally always changing and we should by no means only pay attention to the Penguin, Pandas and Mobilegeddon updates.