condition mean min max ZT0-3 2.69088 2.651435 2.730325 ZT4-7 2.35955 2.35955 2.35955 ZT8-11 3.065885 3.065885 3.065885 ZT12-15 0 0 0 ZT16-19 5.24155 5.24155 5.24155 ZT20-23 3.88672 3.88672 3.88672