A lot of people just want to get an idea for what kind of revenue they can expect by adding Google ads to their site.  The truth is, there are a lot of variables that determine what you will actually earn like traffic, content, how much advertisers are willing to pay to be next to that type of content, ad placement on the pages themselves, whether you are using Google Adsense for Search, number of ad impressions per page, and many other things.  But, when I was looking into this stuff, I realized my "actual results may vary" ... but I just wanted some ballpark examples of what was possible.  That is what this is intended to be ... actual results may vary.

Estimated Annual Earnings From Google Adsense

	Moderate Traffic	High Traffic	Very High Traffic
Typical Site	$100	$1,000	$10,000
Site Related To High Paying Keywords	$1,000	$10,000	$100,000
Site Related To High Paying Keywords & Good Ad Placement	$10,000	$100,000	$1,000,000

Moderate Traffic = 400 impressions/day*
High Traffic = 4,000 impressions/day*
Very High Traffic = 40,000 impressions/day*
*This "impression" count doesn't include traffic from spiders or other bots.  Some analytics tools include these in the total number of page views, so you may not be getting as many impressions if that is the case.  I have read that for an impression to count, all resources (i.e. images, javascript) and iframes have to be loaded, and that is something that most spiders and other bots don't do.

Typical Site & Site Related To High Paying Keywords both use a typical click-through rate of 1.5%.
Site Related To High Paying Keywords & Good Ad Placement uses a click-through rate of 3%.

High Paying Keywords simply means the content of the site is related to keywords that more advertisers are willing to pay for.  Obviously content related to higher revenue industries or products who's demographic is more likely to be on the internet would be more lucritive.  It all boils done to the fact that more of those types of companies are willing to pay to have a link on your site, so you get more of their advertising dollars.

Good Ad Placement just means that the ads are placed in a high profile area of your site.  According to Google themselves, placing your "ad units below the fold, or in an otherwise low-impact location, may result in lower earnings than if the ad unit was placed in a conspicuous location."  You can also use color schemes and other techniques to make the ad area stand out more, and hopefully increase the chances someone would click on it.