condition mean min max ZT0-3 18.4893 15.094000000000001 21.8846 ZT4-7 11.376349999999999 11.376349999999999 11.376349999999999 ZT8-11 8.10756 8.10756 8.10756 ZT12-15 0 0 0 ZT16-19 10.672515 10.672515 10.672515 ZT20-23 13.54025 13.54025 13.54025