TABLE 2.

Ceftolozane-tazobactam MIC distribution for each year of the 4-year surveillance period

Year	No. of isolates at MIC (μg/ml) of:												Total no.	% susceptible	MIC (μg/ml)
	0.03	0.06	0.12	0.25	0.5	1	2	4a	8	16	32	>32			50%	90%
2015	1	3	9	215	449	120	31	18	8	2	1	6	863	98.0	0.5	1
2014			8	51	491	229	62	35	18	3	4	8	909	96.4	0.5	2
2013	2	1	6	43	593	263	94	40	20	6	1	12	1,081	96.4	0.5	2
2012		2	2	39	546	256	73	55	17	3	1	4	998	97.5	0.5	2

^aCLSI breakpoints: S, ≤4 μg/ml; I, 8 μg/ml; R, ≥16 μg/ml.