condition mean min max ZT0-3 16.180725000000002 16.13795 16.2235 ZT4-7 14.51215 14.51215 14.51215 ZT8-11 16.0509 16.0509 16.0509 ZT12-15 0 0 0 ZT16-19 18.8433 18.8433 18.8433 ZT20-23 18.3067 18.3067 18.3067