Welcome back to the second part of our series designed to help you better understand revenue fluctuations. If you're just joining us now, or if you'd just like to brush up on those reporting terms before we dive in again, feel free to visit our previous post from earlier in the week.

Choose the right treatment

You're finished investigating the cause of the revenue fluctuations, and it's time to take action. Find the symptom you identified below for suggested treatments.

Page impression changes
  • Check for AdSense technical issues or public service ads (PSAs). If ads aren't being served on your site, we aren't registering page impressions.
  • Don't miss out on search traffic. Use Webmaster Tools to make sure that Google is properly crawling and indexing your site.
  • Consider the promotions you have running for your site. Did an ad campaign end, causing a drop in traffic? Has a popular site linked to you, causing a spike in page impressions?
CTR changes
  • A drop in CTR can be caused by a user interface (UI) that's not optimized or by poor targeting. Readers won't click on ads they don't see or find irrelevant. To improve the relevance of your ads, you might want to try section targeting.
  • Check for crawl problems. If our system can't crawl your page, we can't serve relevant ads.
  • If you've implemented or changed your ad server, check that there are no new targeting problems.
  • Have you changed the look and feel of your site? Follow our optimization best practices whenever launching a site redesign. An easy way to start is to match the ad colors to the design of your site and choose a top performing unit such as the 300x250 medium rectangle.
  • If your CTR has been in a slow decline, your readers may be experiencing ad blindness. Try testing new ad formats, placements, or colors.
CPC changes
  • CPCs are determined by advertiser bids and are not directly under publisher control. Most large CPC changes are seasonal. For example, certain ad verticals attract more spending during the holiday or back-to-school seasons.
  • CPCs can also fluctuate as advertisers begin and end their advertising campaigns.
  • You can always improve your CPCs by choosing ad formats that support all ad types: text, image, video, flash, and gadget ads. More competition means higher advertiser bids.
Placement targeting revenue changes
  • If overall targeted revenue is changing, determine what your average placement-targeted revenue has been for the past few months. Your goal is to determine if the changes in your recent earnings are part of a trend or a short-term earnings fluctuation.

  • Publishers can experience spikes in placement-targeted revenue when advertisers run limited-time campaigns. For example, an advertiser may run a large placement-targeted campaign only during the opening week of a summer blockbuster movie.
  • If you want to increase placement targeting over the long term, set up ad placements. This will make it easier for advertisers to find and target your site.
Finally, two more things...

Where are the changes happening?

Many AdSense publishers run multiple websites or have site sections that perform very differently. For example, the article section of a cell phone review site may have a higher eCPM than the forums. Whenever you notice revenue changes at the account level, always determine which of your sites or sections is causing the change. You can set up URL and custom channels to track all the important parts of your account separately. Knowing exactly what is changing and where will allow you to make the smartest decisions about what to do.

Taking seasonal fluctuation into account

Take a broader view and look for historical fluctuations in the metrics described above. Over the same time period last month or last year, you may find similar volatility in your eCPM, revenue, or page impressions. For example, you can compare the Mother's Day performance of a flowers and gifts site for 2006 and 2007. Is your current account performance consistent with the previous time range? If so, the revenue change you're investigating might reflect a recurring pattern.

I hope this series will help you get the most out of AdSense, and the next time your revenue changes, I hope it's for the positive.