condition mean min max ZT0-3 40.0113335875 38.255293605 41.76737357 ZT4-7 24.36601993 22.64069843 26.09134143 ZT8-11 37.861608717500005 31.704262184999997 44.018955250000005 ZT12-15 36.278736142499994 35.94167142 36.615800865 ZT16-19 24.6949598825 21.788405935 27.601513830000002 ZT20-23 17.0228305925 15.08346561 18.962195575000003