Statistical Analysis Packages for Libraries

HolyLime writes: I'm a librarian in a small academic library. Increasingly the administration is asking our department to collect data on various aspects of our activities, class taught, students helped, circulation, collection development, and so on. This is generating a large stream of data that is making it difficult, and time consuming, to qualitatively analyze. For anything complicated, I currently use excel, or an analogous spreadsheet program. I am aware of statistical analysis programs, like SPSS or SAS. Can anyone give me recommendations for statistical analysis programs? I also place emphasis on anything that is open source and easy to implement since it will allow me to bypass the convoluted purchase approval process.