We examined data from 17,498 physicians-in-training who reported on 92,662 months of work over a 20-year study interval that included three major revisions to work hour limits. Extended duration shifts (≥24 hours
EDS) are much less common than they used to be. On average, first-year resident physicians (PGY1s) currently work a total of 4 EDS per year and 3 EDS per month during months in which any EDS are worked. This is in stark contrast to the experience of PGY1s training in the early 2000s when the average was approximately 1 EDS per week over the year. More senior resident physicians (PGY2+) have observed concurrent reductions despite their exclusion from the ACGME guidelines limiting EDS. Resident physicians across all levels of training in surgical programs continue to work more EDS than those in medical programs. Similarly, resident physicians on intensive care unit rotations work these shifts more frequently compared to other rotations.