condition mean min max ZT0-3 11.641066666666667 10.014154999999999 13.8336 ZT4-7 7.915315 7.915315 7.915315 ZT8-11 3.817325 3.817325 3.817325 ZT12-15 5.3264725 5.172665 5.4802800000000005 ZT16-19 6.236865 6.236865 6.236865 ZT20-23 11.607949999999999 11.607949999999999 11.607949999999999