condition mean min max ZT0-3 12.510825 11.01685 14.0048 ZT4-7 28.65185 28.65185 28.65185 ZT8-11 24.571800000000003 24.571800000000003 24.571800000000003 ZT12-15 0 0 0 ZT16-19 19.6355 19.6355 19.6355 ZT20-23 23.071649999999998 23.071649999999998 23.071649999999998