condition mean min max ZT0-3 10.321672 10.321672 10.321672 ZT4-7 10.769803 10.769803 10.769803 ZT8-11 10.384575 10.384575 10.384575 ZT12-15 9.492112 9.492112 9.492112 ZT16-19 10.570179 10.570179 10.570179 ZT20-23 9.335431499999999 9.335431499999999 9.335431499999999