condition mean min max ZT0-3 16.383952 16.383952 16.383952 ZT4-7 18.2640825 18.2640825 18.2640825 ZT8-11 17.5614885 17.5614885 17.5614885 ZT12-15 17.687942 17.687942 17.687942 ZT16-19 16.925825 16.925825 16.925825 ZT20-23 18.4586575 18.4586575 18.4586575