Parenteral antimicrobial (A) and antibiotic (B) use at Monroe Carell Jr. Children's Hospital at Vanderbilt. The line marked “Predicted Utilization” represents predicted use based on autoregressive integrated moving average models; the light and dark shaded areas represent 80% and 95% confidence intervals, respectively, for the prediction adjusted for periodicity, seasonal trends, and the overall decreasing trend. The line marked “Actual Utilization” represents actual (observed) use. The y-axis is log-transformed. Abbreviation: DOT/1000, days of therapy per 1000 patient-days.