Although differences in nurse staffing have been associated with individual hospital characteristics in the literature, there have been no studies on how these factors may influence nurse staffing changes made after the mandated nurse-to-patient ratios in acute care hospitals in California. The aim of this study was to determine if changes in medical-surgical nurse staffing (registered nurses and registry nurses) were associated with particular hospital characteristics. Researchers found the baseline level of nurse staffing was the variable most associated with change in mean productive hours per patient day from FY 2000 to FY 2006. Those hospitals with nurse staffing below 4.0 mean productive medical-surgical RN and registry hours per patient day in FY 2000 had a significantly larger, positive change in mean productive hours than did hospitals with average mean productive hours (approximately 5 hours) in FY 2000. Hospitals staffing above 6.0 mean productive hours per patient day in FY 2000 changed their staffing less than did hospitals with average mean productive hours.