"Due to the dynamic nature of Google AdSense, ctr manipulation fluctuations in your revenue will occur. Your earnings will depend on a number of factors, including the types of ads being served to your pages, the cost per click or cost per impression of these ads, and your users' click through selections. Regarding ad placement - the best ad format varies from page to page. We've observed that, in general, wider ads perform better because of their reader-friendly format. We strongly recommend putting your users first when deciding on ad placement. Think about their behavior on different pages, and what will be most useful and visible to them. You'll find that the most optimal ad position isn't always what you expect on certain pages."

Webmasters have very diverse views on how to increase CTR. It largely depends upon the the quality of its content, keywords you are targeting, design and layout of your website, placement of AdSense ads, page optimization and various other factors. Generally, AdSense blocks wrapped between the quality content works the best. For the websites having poor quality content, placing the Ads before the start of the content works best.

Quality Comtent: If you develop a poor quality content website, even if you have high CTR and clicks, you will be getting low priced ads and also nobody will like to add your url to their favorites. But if you have quality content, that keeps the visitors glued, even if you get a little low CTR (not that you will), but you will be getting high priced ads and regular visitors, too. So the bottom is concentrate on providing quality content that provides value to your visitors. For AdSense, quality content is the king.

Proper Ad Positioning: Proper positioning of ads on your website has direct impact on your CTR. Change the location of the ads and watch changes in your CTR regularly. Try to locate the area of the page where the focus of the visitor can be. Generally, AdSense ads near the quality content or other crucial areas like navigation bar tend to perform better. But it really depends upon the keywords you are targeting, and the traffic you have.