There has been widespread concern that clinical notes have become "bloated" with redundant or irrelevant text since the HITECH Act catalyzed adoption of electronic health records (EHRs) in the United States a decade ago. While this concept of note bloat has been widely discussed, there is little evidence on its scope or causes. This retrospective cross-sectional study aims to help fill this knowledge gap by examining the length and redundancy of nearly 3 million outpatient progress notes written between 2009 and 2018 by over 6,000 authors across 46 medical specialties at Oregon Health & Science University.