Ciprofloxacin susceptibility rates over time. It should be noted that statistical results are based on quarterly data. However, for visual clarity, annual susceptibility rates have been plotted for Fig. 1. %S, percent susceptible; Levo, levofloxacin; Gati, gatifloxacin; P. aeru, P. aeruginosa; K. pneu, K. pneumoniae; P. mira, P. mirabilis.