condition mean min max ZT0-3 21.68603333333333 16.788449999999997 26.15795 ZT4-7 19.28545 19.28545 19.28545 ZT8-11 32.10125 32.10125 32.10125 ZT12-15 32.91045 32.05915 33.76175 ZT16-19 25.694699999999997 25.694699999999997 25.694699999999997 ZT20-23 33.7684 33.7684 33.7684