We know that Google changes constantly — they reported over 4,000 launches in 2023 — but what about the internet itself? New content is being created every fraction of a second, spurred in part by advances in AI (for better or worse), and the pace of content creation certainly feels like it’s accelerating. Is it, though, and can we measure it?

The short answer is: yes, and yes. From the end of 2019 to the end of 2024, content churn more than doubled, increasing by +127%. Below is a 5-year chart (by month):

Content churn isn’t an established industry metric, so what are we measuring? For any given day, we’re simply looking at what percentage of URLs (page-one, desktop, Google.com/US) did not appear in the previous 30 days. In other words, what results are new, according to recent history. This was measured across the 10,000 queries in our MozCast research project, which extends back to 2014. These queries tend to be high-volume, so-called “head” terms.

Note the steady climb until Q3 (July) of 2023, with a precipitous drop into Q4 of 2023, followed by another, faster climb to current highs. Summer of 2023 was a period of historically high ranking flux, culminating in an August Core Update, September Helpful Content Update, and October Spam Update. It’s difficult to separate signal from noise, but it is possible that Google pushed back against aggressive content creation that was driving increasing churn.

It’s also worth noting that the end of 2022 saw the public launch of OpenAI’s ChatGPT and kicked off the content generation arms race. It’s very difficult to separate the push and pull of AI content generation and Google fighting back against AI content generation just by looking at rankings, so we’re left to speculate.

Regardless of the cause, content churn immediately began to increase again after this late-2023 drop, reaching a new peak within a year.

You might be thinking that, while churn more than doubled, it’s still sitting at only 2.3% in December 2024. That’s true, but this average daily churn compounds over time. What if we moved the window further back? What does it look like long-term?

Instead of the previous 30 days, what happens when we push the 30-day comparison window back one month, two months, etc.? Looking at December 31, 2024, here’s a graph of how content churn compounds over time:

Pushing back the window 24 months, content churn rises to 48.8%. In other words, nearly half of all page-one rankings on December 31, 2024, were URLs that we didn’t observe for those results two years earlier.

The glass-half-empty view of this is that our hard work as content marketers is becoming obsolete faster. If you’re a glass-half-full kind of person, then it means there’s more competitive advantage to creating and refreshing content.

It’s important to note that average content churn represents a wide range of search intent. Most branded and navigational queries churn very little, whereas search results for newsworthy topics could get rewritten on a daily basis. It’s important to know your own niche and understand its content life cycle.

Regardless of your corner of the internet, content marketing can’t be left on autopilot. Even pillar content that served you well historically is more likely to get displaced in 2025 than it was even a couple of years ago. It’s more important than ever to stay on top of key search results/rankings and how they evolve over time.