Fig. 4

Boxplots showing yearly antimicrobial effectiveness of antibiotics in terms of sensitivity for Gram-negative bacteria cumulatively (for which the drug has been reported) each year. For each antibiotic, boxes represent the sensitivity rate at the 25–75th percentiles (interquartile range), and the ends of vertical lines represent values at the 10^–90th percentiles for the respective year. Horizontal lines represent median values for each year. The comparison of the efficacy of the drug between 2015 and 2021 was done by a two-sample t-test. P =  < 0.05 was considered significant