condition mean min max ZT0-3 10.306113333333332 6.800905 14.282499999999999 ZT4-7 6.827235 6.827235 6.827235 ZT8-11 9.503605 9.503605 9.503605 ZT12-15 14.5088 12.86645 16.15115 ZT16-19 14.94835 14.94835 14.94835 ZT20-23 18.176650000000002 18.176650000000002 18.176650000000002