My sites have been around for a long time and I have a great deal of traffic so that's a big reason why I earn so much. I promote my sites on Twitter, YouTube, Facebook, etc. Making a lot of money with AdSense is all about numbers. The more traffic you have, the greater the earning potential.
My checks weren't always this large. I think my first month's earnings in 2003 totaled less than $20. However, as my traffic increased, so did my checks.
