While we are very proud of the many new clients we have added, our number one priority has always been to ensure the success of our existing clients. From 2002 through 2011, we had an average annual dollar retention rate of approximately 95%, and we believe we are on track to achieve this again in 2012. Our combination of growth and retention helped us increase the size of our user base to over 8 million users in the first quarter, which represents one of the largest SaaS subscriber bases in the world.
We also strengthened our relationships with many of our existing clients during the first quarter, with significant upsales to Pep Boys, Heidelberg Cement, Manchester Airport, one of the largest hospital operators in the world, and one of the largest clothing retailers in the world.
The upsale with Pep Boys is noteworthy because it exemplifies how our product penetration with our clients has become increasingly balanced between learning and our other clouds. Pep Boys began as a learning cloud deal in 2008, and after three successful years with us, they added succession management within the performance cloud in 2011, and in the first quarter of this year, Pep Boys further expanded the performance management footprint within their organization with additional functionality to evaluate the proficiency of new hires.
As our results demonstrate, we have not seen a disruption in our business from the recent consolidation of our market, or from the macroeconomic uncertainty in Europe and other parts of the world. I believe there was some concern among investors that the entry of ERP players into the talent management space, namely SAP and Oracle, could limit our ability to compete in the market. For several reasons, we believe this has not been the case.Read the rest of this transcript for free on seekingalpha.com