condition mean min max ZT0-3 1.3648381666666667 1.1770785 1.667875 ZT4-7 0.42068099999999997 0.42068099999999997 0.42068099999999997 ZT8-11 0.559567 0.559567 0.559567 ZT12-15 0.5243615 0.409613 0.6391100000000001 ZT16-19 0.3747935 0.3747935 0.3747935 ZT20-23 1.129485 1.129485 1.129485