Rank Volatility In the August 2023 Google Core Update

On August 22, 2023, Google announced the release of its August 2023 core update. 

This core update was not only the first one released since March 2023 but also one of the more peculiar updates I’ve seen. The rank volatility trends surrounding the update were unprecedented, which makes diving into this update particularly interesting. 

The Unique Rank Volatility Patterns of the August 2023 Core Update

How impactful was the August 2023 core update? For a bit of context, let’s have a look at the wider volatility patterns surrounding the update. 

Here’s what rank volatility looked like both immediately before and during the August 2023 core update: 

Do you notice anything missing? 

The traditional surge and spike in rank volatility is absent. Typically you’ll see a clear and demarcated spike in rank volatility on the Semrush Sensor a day or two into a core update. 

There is no spike here. The closest thing to it is a late (and fairly common) surge in rank volatility toward the end of the update’s roll-out, circa September 5. 

This is very peculiar in terms of how core updates “behave.”

In fact, if we go a bit farther back in time to mid-July 2023, you’ll see consistently high levels of volatility for over a month. 

That pattern, combined with the absence of the typical “core update volatility spike,” makes the August 2023 core update quite unusual. 

If we pull out the average levels of rank volatility over the past few months, the trend I’m trying to point out becomes vividly clear: an almost unprecedented level of rank volatility not only during the August 2023 core update but immediately surrounding it (which begs the question of how interconnected all of this rank volatility actually is). 

In fact, when we break down the rank volatility levels just a bit and look at some weekly averages since the start of the year, the lack of an “update spike” becomes far more pronounced. 

The July 2023 data above depicts the spike in rank volatility we would expect to occur with a core update.

(This isn’t to say I am concluding the spike was directly related to the core update, but to assume they are completely unrelated doesn’t make sense, either.)

So what you basically see is a huge surge in rank volatility in July that tapers off just a bit in early August before spiking again a few days before the update’s roll-out, with a final receding of the viability elements as the update concluded. 

It’s no coincidence that we see a trend toward typical levels of rank volatility only with the update’s completion. If all of these volatility spikes are unrelated to each other, then with the update’s completion, why didn’t volatility remain high? 

It also makes pinning down its aggregate and relative impact a bit trickier than usual. 

How Volatile Was the August 2023 Core Update? 

Now that we better understand the complexity of that question, let’s dive into some of the data the Semrush analytics team pulled out of the update. 

But before we get into the data, it’s worth repeating that determining the relative impact of a Google update is very complicated and nuanced, despite how the topic is often presented.

There are all sorts of ways to slice and dice the impact of an update; as a rule, you cannot use one metric to determine the impact of an update compared to another update.

And even with multiple metrics, as you can see above, overall levels of volatility surrounding the update will impact the metrics and cloud the data picture. Asking about an update’s impact is a far more complex question than it is often presented. 

With that, here’s our nuanced take on the impact of the update. 

Peak Rank Volatility During Google’s August 2023 Core Update

Let’s start with probably the easiest metric to intuitively understand, the peak levels of rank volatility seen during the August 2023 core update relative to the March 2023 core update: 

Clearly, the August update shows far greater levels of peak volatility than its March predecessor. Back in March, we didn’t have a single vertical show a peak volatility level greater than 7.2. 

Compare that to the most recent update, and we have all but 3 verticals showing volatility levels of 9 or above. Even in those 3 verticals, the lowest peak volatility seen was 7.9, whereas the highest in March was 7.2. 

That shows the August 2023 core update was far more powerful than the March 2023 core update, right?

Wrong. 

This is why context is important—you cannot rely on a single metric to evaluate the strength of an update. 

Have a look at the volatility trends of the two updates side by side. What do you notice (aside from the lack of a traditional spike in August and the presence of one in March)? 

The levels of rank volatility during August were already high. Determining the strength of the updates according to peak volatility in this case simply isn’t a fair comparison. 

Let’s say that the typical update increases the baseline pre-update rank volatility by, for example, 3 points.

If the baseline rank volatility for an update is at 3, it will go up to 6. If the baseline is at 6, then the peak volatility will be around 9. Does that make one update more impactful than the other? Clearly not. 

That’s exactly what occurred in this case. 

So while you’re seeing more volatility overall, it may not be due to the update per se but the overall “volatility environment.” 

This means we need to look at the volatility increase and change relative to the baseline pre-update data. 

Rank Volatility Increases During the August 2023 Core Update 

The next layer in our quest to understand the rank volatility picture painted by the August 2023 core update is to compare the increase in volatility seen relative to the levels of rank fluctuations prior to the update (which, due to the abnormal levels of pre-update fluctuations, we had to go all the way back to a “calm” period in July).

Here’s how changes in rank volatility compare between the August and March core updates:

Comparing the baseline data to the levels of rank fluctuations seen during the update itself, it would appear that the March 2023 core update was more powerful: March saw an increase of 3.3 points on the Semrush Sensor while the August update shows an increase of only 2.8 points. 

And there you have it…except there’s something interesting about this data.

Normally, if one update is “more impactful” than another, it’s pretty universal across all verticals (with maybe one or even two outliers). 

Not so here. 

As you can see above, there are 6 verticals showing a greater increase in volatility during the August 2023 update than during the March update. 

And when we compared the March 2023 core update to the September 2022 core update, there were zero verticals from September showing a greater increase in volatility. 

But even if the pre-update baseline were “typical,” we still wouldn’t have enough data to determine which update was more powerful. 

Why not? 

Because more overall volatility doesn’t necessarily mean that the volatility is more severe.

For instance, maybe there’s a ton of increased rank volatility but it’s all URLs moving up and down in the SERPs a position or two; would that really be something we would call a very “impactful update”? 

Wouldn’t we have to look at how severe the ranking shifts were? 

How Severe Were the Ranking Shifts During Google’s August 2023 Core Update? 

Ask and ye shall receive. 

Let’s have a look at the average position changes during both the August 2023 and March 2023 core updates.

Essentially, the average “fluctuation” moved a URL roughly 3 positions up or down the SERPs. 

Comparatively, back in March the average “fluctuation” stood at 2.7 positions. 

So from this perspective, despite the overall increase and changes in rank fluctuations being greater back in March, the August 2023 core update was more impactful. 

This is supported by the percentage of URLs now ranking among the top 10 results that were previously ranking beyond position 20.

As the below graph shows, nearly 11% of URLs ranking top 10 following the August 2023 core update ranked beyond position 20 prior to its roll-out. 

This stands in contrast to the March update, where just over 8.5% of URLs in the top 10 ranked beyond position 20 prior to that update. 

Continuing the same pattern, 22% of the URLs ranking top 20 post-update are new. Prior to the update, they ranked beyond position 20.

Here too, when we compare the same data to the March 2023 core update, the same pattern regarding the top 10 results emerges: a greater percentage of the URLs ranking top 20 after the August 2023 core update. 

As the data clearly shows, 19.6% of the URLs ranking top 20 after the March update came from the netherworld of the SERPs (i.e., beyond position 20). That number was 22% post-August 2023. 

Thus, from this specific perspective (i.e., how dramatic were the ranking shifts), the August 2023 core update seems to have been “more impactful.”

Are You Confused? 

You should be (sort of). There’s no linear equation for determining how impactful a Google update is. Multiple data points (more than we’ve included here) and the many ways to interpret results can cloud the picture.

On top of that, even with Semrush’s enormously large data set, no one—probably not even Google—can fully understand the impact and changes an update leaves in its wake. 

I hope you now have a better understanding of the impression the August 2023 core update left on the SERPs and the sites that appear there.

But more than anything, I hope you learned that making a determination about an update’s impact is complex, nuanced, and a bit left up to interpretation.