condition mean min max ZT0-3 23.775750000000002 23.775750000000002 23.775750000000002 ZT4-7 17.19305 17.19305 17.19305 ZT8-11 15.31345 15.31345 15.31345 ZT12-15 21.518949999999997 21.518949999999997 21.518949999999997 ZT16-19 19.798499999999997 19.798499999999997 19.798499999999997 ZT20-23 20.176099999999998 20.176099999999998 20.176099999999998