Here’s the short version (in case you don’t have time to read the whole thing):
- Our previous keyword database update (in March) caused a noticeable decrease in search traffic estimations for many websites.
- June’s update will make our traffic estimations go back up (as well as substantially improve their overall accuracy).
- Future database updates should not cause significant swings in our search traffic estimations.
Explaining the swings in search traffic estimations
Ahrefs estimates a website’s search traffic by looking up what keywords it ranks for in Google and calculating how many clicks it gets from each of them. This is why significant keyword database updates can noticeably impact search traffic estimations.
Example
Let’s say that your website ranks #1 for a keyword with 10,000 monthly searches. If we update our keyword database and re-calculate that keyword’s search volume to just 5,000, your site now only gets half as many clicks from the keyword and your traffic estimation will reduce accordingly.
Traffic estimation accuracy
The last time we studied the accuracy of our search traffic estimations, we got a median deviation of 49.52%. This means Ahrefs was often misreporting a website’s traffic by up to half of its true value (read the full study here).
And apparently, the March update decreased our traffic estimations even further:
This was the result of our attempts to improve the accuracy of keyword search volumes in our database (as well as purge some spammy queries). By using more and better data, we realized that our search volume numbers were often inflated—so we decreased them. This had a knock-on effect on our search traffic estimations, which is what caused the drop.
However, we fully understand that we should not improve the accuracy of our search volume data at the expense of our search traffic estimations. So, in June’s keyword database update, we’re determined to improve both.
Expect the search traffic estimations (and trend graphs) to go up
Because of that latest database update, our search traffic estimations are further off than they were before (according to our internal research). We plan to improve this in the upcoming database update, so you can expect the traffic estimations in Ahrefs to increase across the board once it’s rolled out.
Please note though, that this database update will affect our traffic estimations in two ways.
First, the updated search volumes of all existing keywords in our database, will cause the historical data of all websites to move accordingly:
Second, the new keywords that we’ve added to our database in this update might cause a spike on the traffic and keyword graphs for some websites:
It is also important to point out, that if your website’s metrics were affected by these changes - all other websites in your niche were also equally affected. Which means that the below formula still holds true.
Please also make sure to activate “Ahrefs updates” notes on the graphs in Site Explorer, so that you could easily see if the traffic spike was caused by our latest database update:
Got questions? Feel free to start a discussion in our community, or ping our support team via the chat button inside Ahrefs.
