condition mean min max ZT0-3 21.216949999999997 21.1022 21.331699999999998 ZT4-7 9.874134999999999 9.874134999999999 9.874134999999999 ZT8-11 7.07457 7.07457 7.07457 ZT12-15 0 0 0 ZT16-19 17.29575 17.29575 17.29575 ZT20-23 18.82425 18.82425 18.82425