condition mean min max ZT0-3 5.903191666666667 4.70983 6.8151600000000006 ZT4-7 2.70206 2.70206 2.70206 ZT8-11 3.940795 3.940795 3.940795 ZT12-15 4.8965975 4.28918 5.504015 ZT16-19 3.54871 3.54871 3.54871 ZT20-23 4.7344550000000005 4.7344550000000005 4.7344550000000005