condition mean min max ZT0-3 2.42122484325 2.0402153715 2.802234315 ZT4-7 5.52582213125 3.910529082 7.1411151805 ZT8-11 8.972533551 7.9778004424999995 9.9672666595 ZT12-15 10.84978726125 8.519520687 13.1800538355 ZT16-19 5.71936626925 5.466188676 5.9725438625 ZT20-23 8.06012466725 7.5156385375 8.604610797