condition mean min max ZT0-3 5.101266666666667 3.22433 6.30154 ZT4-7 2.18263 2.18263 2.18263 ZT8-11 3.312995 3.312995 3.312995 ZT12-15 5.1044325 3.64798 6.560885 ZT16-19 5.96648 5.96648 5.96648 ZT20-23 6.540665000000001 6.540665000000001 6.540665000000001