2011 was what we called internally, the year of construction. There were 3 principal themes to our work. First, reduce cost and improve the productivity by doing more with less. Second, reduce our debts to deleverage the company. And third, adopt and implement a strategic approach that will affect the transformation of SuperMedia from a provider of Yellow Pages products to a trusted marketing adviser helping small- and medium-size businesses retain and add customers using the full spectrum of digital and traditional media. I've spoken to you about our prior of each of these scenarios during prior quarterly calls. Now, let's take a look back at the results for the whole year.
We attacked our cost structure making disciplined decisions about products and activities that should be eliminated. And also work intelligently to create efficiency in how we operate. I'm pleased to say that all departments participated in these initiatives. And everyone deserves the credits for the company's 420-basis-point year-over-year margin improvement. As a result of these reductions, we delivered 2011 annual adjusted EBITDA of $602 million, 7.5% less than in 2010, despite an 18% year-over-year decline in adjusted revenue. As reported previously, 2010 included a $40 million favorable non-recurring non-cash resolution of state generating tax claims. We paid equal attention to our debt and capital structure. Again, the results are good. We reduced our debt by $426 million over the course of 2011.
In total, we have now taken down over $1 billion in debt since January of 2010. We intend to continue to pursue further reductions in 2012. Good work on expense and debt reduction has been complemented with a coordinated effort by marketing, sales and operations to transform our approach and value proposition for our clients. This is the path to improving our top line results. As a company, our purpose always has been to help small- and medium-sized businesses attract and retain customers through local media. That remains unchanged. Our job is to bring clients leads and customers, so that they can focus on what they do best: Running their businesses.